What if Japan attacked the Dutch East Indies in 1936?

[raharris1973]

What if Japan had attacked the Dutch East Indies in 1936, based on lobbying from the Navy to gain the valuable archipelago located at the strategic maritime crossroads of the Indian and Pacific Oceans, offering Japan a position outflanking Singapore and Manila Bay, and providing already extensively developed fuel resources to fuel Japan's Navy, Army, and economy under Japanese, rather than foreign control, and coincidentally, offering Naval Admirals, Captains and other officers a chance for glory and promotion?

Considered as a one-on-one struggle, as of 1936, Japan should be completely confident in its ability to win a near term victory over the Dutch in the East Indies, conquer the territory, and hold it against a Dutch counter-attack, given the distance any Dutch relief force would have to travel.

The archipelago's distance from Japan's land-based airbases would be a serious operational and logistic problem to overcome, and least for the most valuable, populous, and productive western and central islands of the East Indies, although IJN carriers could project limit airpower against most parts of the islands from the beginning. Engaging against enemy land-based air power in the defense with only carrier-based air would be risky and hazardous however.

An operational solution could be found, without stepping on the territory of other powers, like Britain, the USA, or France, by rapid successive sequential operations starting in the easternmost of the Dutch East Indies, where land-based Japanese aircraft (likely naval rather than army, but still land-based) could provide powerful support from bases in the Japanese Micronesian Mandated islands to back up combined Special Naval Landing Forces supported also by carrier-based aircraft and battleship bombardment, to rapidly capture Dutch airfields for Japanese use.

The Japanese, bringing along engineering troops, could follow up each successive island group seizure with rapid repairs of Dutch airfields, forward transport of land-based air, and attack on the next Dutch-owned objectives, in support of the Combined Fleet and landing forces.

A rapid pace of maneuver would be essential to keep defeating the Dutch in detail and prevent defensive consolidation, and reduce time for other powers to consider possible intervention in the bilateral conflict.

Once all the principal islands were secured and the major Dutch forces in the region defeated, their continued occupation would be a fait accompli, and peace treaty and war termination with Netherlands would be a diplomatic formality in all likelihood. The Netherlands, despite being an economic and financial power, were not a vast manufacturing, military, nor territorial power, nor highly populous and thus in a position to undertake a long-distance reconquest of the East Indies.

After establishing occupation, Japan could repair damaged facilities, reorient the oil and food exports to the Japanese imperial market, and theoretically emerge stronger and self-sufficient, having a naval/maritime complement to the Army's Manchukuo project.

Well, that's sounds great, so why didn't Japan do it? What could go wrong?

• Wasn't Japan bogged down in a war with China in 1936?
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• As it turns out, if it was a war, it was not a very hot one at this time. Japan enjoyed control over the Manchukuo and Inner Mongolian (Mengjiang) puppet states north of the Great Wall of China, and had compelled China to keep large parts of Beijing's province of Hopei demilitarized under the He-Umezu truce agreement. For most of 1936 until the Xi'an incident of December, Chiang remained preoccupied with preparing an encirclement and annihilation campaign against the Communists who had survived the Long March in Shaanxi province and ignored calls to push back against Japan. Chiang did not start pushing back against Japan until July 1937, and the Japanese were not getting political signals he might be heading in that direction, until after he paused anti-Communist operations during/after the December 1936 Xi'an incident and increased resistance and unity talk.
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• What about intervention of other powers, like the USA or Britain, the Philippines, Malaya and Borneo are in between the Dutch East Indies and Japan you know?
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• The Japanese could quite plausibly calculate by this time, middle or late 1936, that none of these powers would intervene directly or effectively in a Dutch East Indies war, no matter what they said. Such a calculation could quite plausibly be correct. It would give us a pair of equally interesting scenarios if the Japanese calculation turned out to be correct, OR, if it turned out to be incorrect, and another power intervened in the war.
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• Why should Japan have confidence in non-intervention by outsiders? 1) Outside powers and the League of Nations had not militarily intervened, nor economically sanctioned Japan over the Manchurian invasion of 1931-33, and the adjunct short-term Shanghai invasion, despite diplomatic condemnation. 2) More recently outside powers had not intervened militarily, or sanctioned effectively or persistently, against Italy's invasion of Abyssinia, and ultimately its annexation from 1935-to April 1936, despite condemning it. They tried some sanctions but did not persist. Relevant to Japan's situation, Abyssinia was adjacent to British and French colonies, but still they permitted Italy to expand next to them and to use Suez. This might be explained away by economic or racial factors. Cynically, Abyssinia was poor and hardly exported anything, so maybe it wasn't worth a struggle to London and Paris, but the East Indies produced valuable petroleum and hardwood and limited rubber, rice and coffee exports of greater commercial value. Or perhaps white leaders in London, Paris, Washington could tolerate white Italians conquering black Africans, but not tolerate Asians ousting white Dutch rulers to take control over a large Asian people and Asian land. But other events of the 1930s suggested that weak will in the west and aversion to conflict was about a more general preference than just racial bias: 3) In 1934 (or 1935?) Britain had signed the Anglo-German Naval Treaty, showing a lack of determination to hold its full degree of naval superiority over Germany, even in the North Sea close to home, and 4) In 1936, France (and Britain) failed to resist the German remilitarization of the Rhineland, right upon her border, closer than the metropolitan Netherlands is to France, making any concept of Paris or London extending deterrence out to a distant Dutch *colony* less credible and more of a stretch. 5) All West European powers showed preoccupation from July 1936 onward, with the Spanish Civil War, which was turning out to be a protracted struggle, not a quick coup d'etat. Germany and Italy were intervening directly in support of the Spanish Nationalist rebels. The British were pulling the French into the unsuccessful Non-Intervention Committee and policy, to try to contain the conflict, and not actively countering Italo-German influence or encouraging France to do so (in fact discouraging it). As another bonus from a Japanese point of view, the Spanish Civil War was drawing heavy attention from the Soviet Union and allied ideological movements, leading to deployment of Soviet advisors, weapons and international volunteers, which diverted Soviet attention from northeast Asia and the Manchukuo-Korea frontier.
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• This accounts well for the alternate preoccupations and likely hesitations of European powers to intervene in the Indies. What about the USA? From a Japanese vantage point, the Roosevelt Administration's first term had been almost exclusively focused on domestic policy, not passing anything like a two-ocean Navy bill, with any naval construction advertised more as a jobs program than a security program. FDR was preoccupied with his reelection. If anything, his foreign policy as shown in the Americas, was one of retrenchment from intervention in neighbors' political affairs. With respect to the Far East, the Americans formally set a timetable for the independence of the Philippines in 1945, through the Tydings-McDuffie Act of 1935. Despite some posturing of the US Navy at the tail end of the Hoover Administration during the Shanghai affair, and the failure of any Naval talks in the mid-30s, the relative quiet that had settled on the China-Manchuria front since 1933 had not added any particularly urgent stressors to US-Japanese relations by 1936. America was somewhat economically recovered from its depths of 1933, but hardly looking outward, except for trade opportunities, which it sought with Japan as much as with China and European colonies like the DEI.
• And in case, should any of these powers, America, Britain, France, the USSR, turn against Japan in the medium term or long-term, the Dutch East Indies would be a great strategic asset for Japan to possess from the beginning of any serious conflict escalation, rather than not to have.
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• Didn't the Japanese Army, not Navy, run everything in 1930s Japan?
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• It's more complicated than that. Army officers and societies organized and roamed free making up their own foreign policy as they went along (like the Manchuria incident of 1931, and earlier and later incidents), assassinating politicians and generals they felt insufficiently supportive, and attempting coups d'etat, from the 1928-1936 timeframe. But so did some Navy officer groups and societies. In February 1936 a spiritualist Army faction attempted a coup and made some headway, but was suppressed by an angry court, Army senior command, and Naval forces. The plotters, unlike in previous cases were sternly dealt with, being either executed or forced to commit suicide. The result was sort of a compromise, since the Army coup was stopped, but only with the help of other parts of the Army, with ideas not 100% dissimilar from the plotters. Initiative coups and assassinations of politicians and generals pretty much ceased at this point from military personnel. But people always worried they could happen if top leaders adopted policy broadly unpopular with the Army or Navy. The Army and Navy generally had different priorities, but both got increased funding and their share of personnel and equipment budgets, and policy influence, in the spoils system.
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• When considering Japanese military factions and their different priorities, and the Japanese Navy and Army and their different priorities and positions, it is important to remember that differences =/= diametrical opposition and differences =/=mutual hatred. Neither service was a monolith, and both Army and Navy contained "Go North" and "Go South" advocates and it is easy to provide quotes from both.
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• Edward Drea, writing on this era has noted that one of Emperor Hirohito's recurring critiques and lines of questioning toward the Army regarding its course of action in Manchuria and China was whether Japan was overreaching and investing in an unbalanced commitment to the Army in the mainland, and not taking enough care to keep Japan's Navy and Air forces and maritime position adequately strong to deal with possible threats to Japan's interests from the USA or Britain.
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• So, I could imagine it being plausible that a strong, enterprising Navy-centric group, joined by some Army officers and Civilian officials with similar ideas and economic justifications, could build a powerful case for domination of the Dutch East Indies in the mid-1930s.

 

[raharris1973]

If Japan did launched this fight in, for example, December 1936, and completed its invasion occupation of the DEI in about 10 weeks or three months, which seems a generous amount of time for Dutch resistance if Japan is focused on this one objective, Britain's Australian Dominion would be the most freaked out. The Empire is already in shock from the abdication crisis, but bold "yellow peril" showing up just to the north makes this look trivial by comparison.

Australia, with its Papua New Guinea Mandate, the Malaya and Borneo colonies, and the Dominion of India would want reassurances from Britain. The Singapore base would be outflanked. The Americans would similarly be disturbed and find the Philippines with Manila Bay, Subic Bay and Clark Airfield surrounded in a Japanese-controlled arc running north, east and south of the islands from Taiwan/Formosa to the Mandates to the East Indies.

In the event of European war or crisis, India, and Australia and New Zealand especially, would have enough home defense worries to make it unlikely they could spare any troops to support the British Empire outside of their home Indo-Pacific region. Australia and New Zealand would probably seek closer diplomatic ties to the USA for their own security, and many in the US Roosevelt Administration, State Department and Navy would like the idea, considering the extra exposure and vulnerability of the Philippines and America's other scattered Pacific possessions, but America's extant defense posture as of 1936 is very weak and the idea of commitments outside the hemisphere is very controversial.

France would be highly concerned for its Indochina colony, but would be able to spare little for it, already struggling to rearm to deal with the growing German threat in Europe, Italian naval competition in the Mediterranean, and trying to prevent spillover from the Spanish Civil War drawing France into war or internal conflict.

The Japanese military and Kempeitai (secret police) and bureaucrats and zaibatsu will have plenty to do in the occupation of the DEI and its restoration to full production. To the degree Tokyo and senior Army staff are turning the dial on pressure with the frontier with China in early 1937, they may not press it as much as historical because of other available adventures and tasks in the Indies. However, the escalation to full-scale war in China in OTL July 1937 was multi-sided. It was not driven only, or even primarily, by Tokyo based Army commanders trying to alter the previous status quo, but by initiatives and overreactions by local Japanese commanders, and by this point, just as important, a Chinese Nationalist side that was determined to demonstrate it was not going to take it lying down anymore. So, any lack of outbreak of Sino-Japanese war in July 1937 would probably be no more than a delay, not total prevention.

The Japanese presence in the DEI would almost certainly stimulate earlier than historical British and American naval building oriented toward Indo-Pacific defense. For Britain, it is likely to make her lean harder into appeasement, if that is somehow possible.

When the probable Sino-Japanese War breaks out, the additional pre-existing Japanese occupation of the East Indies could cut two opposing ways for British and American policy. On the one hand, since the Japanese "cat" is among their colonial "pigeons" more boldly and dangerously placed, the priority on building up defenses of Australia, Malaya, the Philippines, and Japan's obvious ability to lash out may mean London and Washington are more hesitant to aid China and have less to spare. Equally or more likely, they may see supporting the Chinese resistance as a greater imperative than OTL, and do more of it, earlier. In any case, I would expect Soviet support for China to be similar to OTL.

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[Sekhmet_D]

I guess the question is: was the 1936 era Japanese military technologically and knowledgeably capable of enacting such an operation?

Without the combat experience the Japanese gained from four years of warfare in China, not to mention certain items of equipment that they only invented after 1940 like the A6M fighter and G4M bomber, I daresay attempting to seize the NEI five years ahead of the OTL schedule is not going to go as smoothly for them as one might think.

 

[YYJ]

I suppose they could, but there is a lack of motive. The US was selling Japan 80% of their oil needs, and were happy to sell Japan as much oil as they wanted. Japan was buying oil from the DEI, but got pushy in the negotiations and was irritated that the could not force the Dutch colony to give them special concessions in September 1940. Japan had a supply of oil from the United States until June 20,1941, when the US stopped shipping oil from regions that had shortages, for domestic reasons. Then the US froze Japanese assets on July 25, 1941 and embargoed all exports to Japan on August 30, in response to Japan invading French Indochina.

The Greater East Asia Co-Prosperity Sphere was a concept first mentioned on June 29, 1940.

All these events come half a decade after 1936.

This is a table of US exports to Japan, in thousands of $

https://www.researchgate.net/figure/US-export-to-Japan-in-major-items-1930-1941-thousand-dollars-Source-Hosoya-Saito_fig1_330839251

This paper talks about the economic events leading up to the Japanese attack on the US, but the escalation started when the European war was already in progress.

https://faculty.cc.gatech.edu/~tpilsch/INTA4803TP/Articles/Oil%20Logistics%20in%20the%20Pacific%20War=Donovan.pdf

 

[raharris1973]

I suppose they could, but there is a lack of motive.

The Greater East Asia Co-Prosperity Sphere was a concept first mentioned on June 29, 1940.

While the GEACPS concept was not articulated until the time you mentioned, expansive interest in Southeast Asia, and concepts of Southeast Asia as containing essential economic resources for Japan went back future to the New Order in Asia concept (1936) and Nanshin-ron concept going back to the late 19th century.

Nanshin-ron - Wikipedia

en.wikipedia.org

So, while a fully articulated plan for all Southeast Asia seizure was not worked out and pursued until WWII in Europe began, the importance of the region to Japan was recognized at one level. Japanese Naval war planning since 1907 had fixated on the United States (and some may have been done since 1899 or so) and from an early point, it dwelt on landing operations in the Philippines and Guam, to seize as bait for the US fleet. Geographically, the Philippines are not far from the Dutch East Indies. Included in the in the Japanese Navy (IJN)'s calculation of the US as the most likely and most dangerous eventual foe, a logical assumption would be that while peacetime trade with the USA in everything, including fuels, is just fine, in wartime with America, no American fuels or metals would be available. - rendering all the peacetime oil import statistics irrelevant, except for pre-war stockpile building.

I have not seen the direct data on it, but at some point after Britain terminated the Anglo-Japanese alliance in 1922, the Japanese Navy started doing contingency planning against Britain and its main regional bases like Singapore. [Britain certainly started contingency planning, and infrastructure building, to counter Japan by the 1930s] Japan probably had at least rudimentary anti-British, anti-Singapore plans on the shelf by the time of the Shanghai incident of 1932 and the Lytton Commission report that year.

Geographically, it is not much of a stretch from having Philippines or Singapore related plans to developing a new, East Indies focused plan.

I guess the question is: was the 1936 era Japanese military technologically and knowledgeably capable of enacting such an operation?

That is a good question: Just what kind of operations are the Japanese services capable of mounting in 1936, in terms of sortie'ing the fleet, conducting battleship bombardments to shore, bombarding targets on land with carrier-based aircraft, destroying foreign naval opposition and air forces, conducting amphibious landings, seizing, repairing, and using formerly enemy held airfields, and so on.

They had a certain skill level at this type of thing in early 1942 after years of war in China, and a constantly updated equipment set, and doing some coastal landing operations on a smaller scale than this. We cannot assume with lesser experience, and earlier model equipment, they would demonstrate the same capability in 1936 and 1937 they demonstrated in 1942.

And at the same time, we have to ask ourselves, what kinds of assaults are the Dutch forces in the various parts of the East Indies archipelago capable of defending those islands from, and what tools in terms of ground, sea, and air forces do they have on station to meet an assault by an invader with modern weapons, and how much warning do they need to be at all ready?

Without the combat experience the Japanese gained from four years of warfare in China,

Right - the Japanese experience would be more limited - They would have ground and air experience from the Manchuria war against lesser warlord forces, 1931-1933, and there might have been over-beach operations on the Liaotung peninsula, but maybe not. They would have had landing and urban combat experience and ship to shore and ground to air combat experience from the Shanghai incident of 1932. But they would lack any of the further experience from the 1937 bigger scale Sino-Japanese war. Their higher level officers and senior non-coms could have landing, ground, and technologically primitive air experience dating back to the Siberian intervention of 1918-1922 or the WWI Pacific/China campaigning of 1914, or ground or naval combat from the Russo-Japanese War. Plus, any exercises and maneuvers with more recent technology in the 1920s and 1920s. It is noteworthy that in the 1920s while China and Russia both seemed very weak and hamstrung, the Navy, rather than the Army, was the senior service in Japan, the the Japanese Navy got priority for exercises and maneuvers testing its amphibious landing and island defense concepts in mandates against the top perceived enemy, the USA, over the Army's priority exercises. It was only after the Sino-Soviet border war of summer 1929 that the situation on the mainland began to look threatening enough that the Army regained priority in Japan.

Against this, the Dutch had no post-Napoleonic combat experience, except colonial against indigenous rebels.

items of equipment that they only invented after 1940 like the A6M fighter and G4M bomber,

Certainly, none of this would be available. A war starting at the tail end of 1936 would have to be fought more or less with the same naval ships, fighter aircraft, bomber aircraft, infantry weapons, light and heavy artillery, infantry vehicles, armored vehicles, logistics, and small arms as Japanese Navy forces and Army forces used in the first year of the Sino-Japanese War starting from July 1937 onward, and this equipment would go up against whatever the Dutch possessed at the time and anything else allies might get in their hands while the fighting goes on.

I daresay attempting to seize the NEI five years ahead of the OTL schedule is not going to go as smoothly for them as one might think.

I would not expect it to be as fast as the OTL Feb-Mar 1942 conquest. Nor mistake free on the Japanese part. Nor without the occasional Dutch tactical victory.

But without intervention by an outside stronger power, I think Japanese victory, Dutch defeat is assured.

Consider why from a different angle - Japan can project a significant force to one part of the DEI, the east, and from there, to the rest. It lately demonstrated that amount opf expeditionary capability in Manchuria and Shanghai earlier in the 1930s. Japan also demonstrated expeditionary warfare capability at a much lower technology level than 1942, with its siege of Qingdao from September-November 1914. And Japan's Navy demonstrated its logistic capability to simultaneously seize widely separated, by thousands of miles, enemy island objectives, in the space of a single month, throughout the Pacific, under the relatively low technology conditions of October 1914, with a limited number of radios and reconnaissance aircraft. Japan's starting points towards German Micronesia from the Bonins in 1914 is pretty comparable to its starting point in the Palaus to the Dutch East Indies, and while its 1936-37 forces won't have 1942 levels of aircraft, radio, or other tech, they'll be much more lavishly tech'ed up than the Japanese forces of 1914. To be fair to the Dutch, the main advantage they will have in defense is that they present larger targets with more depth, requiring large invasion forces, and possessing larger garrisons and police forces than German Micronesia had in 1914. But size would be a double-edged thing for the Dutch. Bigger islands mean more potential landing zones to guard. There may be more defenders or more local labor to set to defensive works, but only the Dutch and Eurasians and probably Chinese are truly reliable supporters of the Dutch defense. Most natives will be pretty indifferent.

 

[Garrison]

Catastrophic fail because given the geography there is no way the British can afford to allow the occupation of the DEI and the RN would be able to overpower the IJN. Also attacking the DEi without already occupying Indochina is going to be a challenge. Overall this is guaranteed to provoke action from the British, French and the Americans.

 

[nbcman]

If it is in 1936, the IJN would have the following CVs/CVLs based on OTL per http://www.combinedfleet.com/cvlist.htm.
Hosho - in drydock until April 1936 Undergoing sea trials for probably 3 months so probably available July 1936.
Ryujo - in drydock until June 1936. Sea trials until September 1936.
Kaga - available.
Akagi - in drydock for extensive modifications Oct 1935-Aug 1938.
Remaining CVs used in 1941 are either in the process of being built (Soryu & Hiryu) or not laid down yet.

In addition, the invasion would be based on Formosa since there were no closer Japanese bases. So definitely no land based air support in 1936. And it would be 1500+ miles from Formosa to the DEI or slightly less from Palau - both of which pass the Philippines which the Japanese planners felt they needed to attack in 1941.

 

[Sekhmet_D]

Also attacking the DEi without already occupying Indochina is going to be a challenge.

This is a very important point that even I overlooked.

IOTL, the Japanese invasion forces for South East Asia embarked from Cam Ranh and the JNAF units that attained air superiority over the NEI conducted their initial raids from captured American facilities in Davao before they leapfrogged further south to Tarakan, Menado, Balikpapan and Kendari.

Japan has neither Cam Ranh nor Davao as bases in 1936. Without the Second Sino Japanese War occurring in this hypothetical scenario, they don't even have Southern China to use as a staging ground. The only one they possess is Formosa, which is a hell of a way away from the NEI.

The only viable plan with Formosa as staging ground would be to quickly seize Tarakan and Balikpapan as sufficiently central locations from whence the other islands in the NEI can be air raided and invaded. And even that is a very dicey prospect given the aforementioned distance from Formosa.

 

[Garrison]

Other thing to remember with the DEI is that the British have colony on Borneo, which IOTL was a major Japanese objective because of the oilfields, I can't see how they could go round it in 1936, even if they wanted to.

 

[raharris1973]

Catastrophic fail because given the geography there is no way the British can afford to allow the occupation of the DEI and the RN would be able to overpower the IJN. Also attacking the DEi without already occupying Indochina is going to be a challenge. Overall this is guaranteed to provoke action from the British, French and the Americans.

Royal Navy intervention would likely halt Japanese progress through the Indies short of even short-term success. American interference alone would doom Japan's effort in the long run despite any short term successes, and would likely encourage participation of others on the American side. French participation alone would be a complicating factor for the Japanese but would not be decisive. But France intervening on Dutch behalf without the UK or US moving first is vanishingly unlikely. France would only move in the region as a decidedly junior partner to other powers, with more at stake, primarily to earn diplomatic leverage/commitments pertaining to Europe.

Regardless, intervention by *any* of the trio requires a political decision and political will to exert the effort in a timely manner before Japanese conquest of the islands makes it a fait accompli [aid to the Dutch while they last, economic sanctions, protests, and building up regional defenses and forces are much cheaper, easier alternatives also]. No matter how geographically and strategically advisable or obvious the wisdom of British intervention is, does not guarantee a political decision to make it happen. It could happen, I won't absolutely rule it out.

 

[raharris1973]

Other thing to remember with [northeast Asia south of the Amur river] is that the [Soviets have a province right on the Sea of Japan, right next to Korea, and east of Manchuria], which IOTL was a major Japanese [security concern because of the vital port of Vladivostok and major Soviet airfields and naval bases threatening Japan and its shipping]. I can't see how they could go round it [to Manchuria] in [1936 1931-32], even if they wanted to.

The method of the Japanese going around British Borneo if they want to is rather simple. It consists of traveling to Dutch Borneo (and Dutch New Guinea and Timor for that matter) by sea and air approaches hitting only their Dutch owned coasts and performing ground combat operations with units competent at land navigation (and staying on the Dutch sides of the borders), and carrying compasses and including surveyors, sorts of things they need and want for artillery aiming anyway.

The thing about island objectives is that is even easier to pick and choose to seize them a la carte, taking some, and not others in between, than it is to do with land targets [especially when they are under separate sovereignties and you have local naval superiority], yet for some reason people are obsessed with the insular Southeast Asian islands and Western Pacific islands being an inseparable, sequential "set" that have to rigidly be taken stepwise north to south. I would note, and this is easily to locate in the Army "green book" on the pre-Pacific War situation, that the Japanese planned multiple variations for their Strike South campaign, and while they did end up using the two prongs south approach that arrived at the East Indies convergently after seizing Malaya and Singapore and British Borneo, and most objectives in the Philippines, they had other plans they were not to embarrassed to commit to paper, included one that involved striking furthest first, occupying the DEI, and rolling back up to the Philippines and Malaya. They also had a "clockwise advance", Philippines-DEI-Malaya axis, favored by many in the Navy, and a "counter-clockwise advance", a Malaya-DEI-Philippines acis favored by most in the Army.

 

[raharris1973]

If it is in 1936, the IJN would have the following CVs/CVLs based on OTL per http://www.combinedfleet.com/cvlist.htm.
Hosho - in drydock until April 1936 Undergoing sea trials for probably 3 months so probably available July 1936.
Ryujo - in drydock until June 1936. Sea trials until September 1936.
Kaga - available.
Akagi - in drydock for extensive modifications Oct 1935-Aug 1938.
Remaining CVs used in 1941 are either in the process of being built (Soryu & Hiryu) or not laid down yet.

Thanks for the good, valuable ORBAT info

In addition, the invasion would be based on Formosa since there were no closer Japanese bases. So definitely no land based air support in 1936. And it would be 1500+ miles from Formosa to the DEI or slightly less from Palau - both of which pass the Philippines which the Japanese planners felt they needed to attack in 1941.

This is a very important point that even I overlooked.

IOTL, the Japanese invasion forces for South East Asia embarked from Cam Ranh and the JNAF units that attained air superiority over the NEI conducted their initial raids from captured American facilities in Davao before they leapfrogged further south to Tarakan, Menado, Balikpapan and Kendari.

Japan has neither Cam Ranh nor Davao as bases in 1936. Without the Second Sino Japanese War occurring in this hypothetical scenario, they don't even have Southern China to use as a staging ground. The only one they possess is Formosa, which is a hell of a way away from the NEI.

The only viable plan with Formosa as staging ground would be to quickly seize Tarakan and Balikpapan as sufficiently central locations from whence the other islands in the NEI can be air raided and invaded. And even that is a very dicey prospect given the aforementioned distance from Formosa.

I am a little frustrated with the obsessive, almost monomaniacal, focus on the Taiwan, Indochina, generally South China Sea avenue of approach for nnaval forces and troop convoys and ground-based air support, as if it is the only option. It's not.

You make these statements about geographical/operational constraints without even quoting paragraphs 3,4,5 and 6 of the first post in the thread, even for rebuttal purposes, even though they were written to preemptively address objections/complaints such as yours. Were they TLDR for you? Are you just headline reader/reactors, not post/content readers? I read stuff before I start making arguments.

Do you think the Mandated islands Japan owned from WWI through the entire interwar era, especially the Palau islands in their southwestern portion, did not exist, or somehow could not stage air or naval forces for operations further afield?

Are you saying the lines illustrated on these maps from the OTL WWII Japanese "centrifugal offensive" in Southeast Asia and the western Pacific are lying, deceptive, misleading?

File:Second world war asia 1937-1942 map en6.png - Wikipedia

en.wikipedia.org

Map of WWII: The Dutch East Indies Dec 1941 - April 1942

https://i0.wp.com/amti2016.wpengine.com/wp-content/uploads/2015/08/3.jpg

With reference to the third map in particular, and Japan's ability to move on the DEI being hamstrung by not having Davao in the Philippines in 1936 (unlike 1942), guess where the Japanese force that took Davao from the American/Filipino forces after Dec. 8, 1941 came from?

The Palau (Pelelieu, Koror, Anguar) an island group the Japanese had owned since 1914. Forces from here also assaulted Legazpi in southeastern Luzon. Both the Davao and Legazpi operations (and early operations from the Carolines in OTL against Australian owned Bismarcks and New Guinea) were conducted at ranges easily reaching several eastern islands of the Dutch East Indies.

 

[YYJ]

I would think that a 1936 naval war would still be more of a battleship and cruiser war. The naval aircraft are not quite mature enough to do 1941 damage.

On the Japanese side, the Type 93 torpedo had been in service since 1933. It would be a nasty surprise, like it was in OTL 1942.

 

[Garrison]

The method of the Japanese going around British Borneo if they want to is rather simple. It consists of traveling to Dutch Borneo (and Dutch New Guinea and Timor for that matter) by sea and air approaches hitting only their Dutch owned coasts and performing ground combat operations with units competent at land navigation (and staying on the Dutch sides of the borders), and carrying compasses and including surveyors, sorts of things they need and want for artillery aiming anyway.

Right because the British are stupid enough to trust that they won't change their mind and again their mere presence in the DEI is threat to Singapore and Malaya. This on the level of one 10 year old poking another with a ruler and declaring 'see I'm not touching you' and then being surprised when they get smacked in the face...

 

[HJ Tulp]

The Japanese could quite plausibly calculate by this time, middle or late 1936, that none of these powers would intervene directly or effectively in a Dutch East Indies war, no matter what they said. Such a calculation could quite plausibly be correct.

While it should be possible to construct a scenario where neither the UK or the US would intervene, these will not be the most likely, and thus it is very questionable if the Japanese would risk it. Don't forget, in WWII the Japanese government didn't know for sure that the US would contest its SLOCS between SEA and the South, but was unable to ignore that possibility.

And at the same time, we have to ask ourselves, what kinds of assaults are the Dutch forces in the various parts of the East Indies archipelago capable of defending those islands from, and what tools in terms of ground, sea, and air forces do they have on station to meet an assault by an invader with modern weapons, and how much warning do they need to be at all ready?

The land forces of the KNIL were very much at their lowest point, after years of Great Depression-induced budget cuts. From 1936 budgets increased, though new material was slow to arrive. This does mean that the KNIL isn't caught mid-reform as IOTL and is this much more cohesive, though naturally less well armed.

The air component of the KNIL was receiving the Martin 139 bomber from September 1936 on out. While this machine was severely outclassed in WWII, at the point of delivery it was pretty good.

Like the other parts of the DEI-defense, the Royal Netherlands Navy had suffered much during the Crisis Years. What does help it though, is that these were the golden years of the submarine-based doctrine. Not enough to stave of the combined might of the Japanese navy, army and airforce no, but it could very well give the Japanese invasion force a bloody nose.

I have some more thought but for that I will need my sources and I'm currently - and happily - on holidays so that will have to wait a few weeks.

 

[raharris1973]

While it should be possible to construct a scenario where neither the UK or the US would intervene, these will not be the most likely, and thus it is very questionable if the Japanese would risk it. Don't forget, in WWII the Japanese government didn't know for sure that the US would contest its SLOCS between SEA and the South, but was unable to ignore that possibility.

The land forces of the KNIL were very much at their lowest point, after years of Great Depression-induced budget cuts. From 1936 budgets increased, though new material was slow to arrive. This does mean that the KNIL isn't caught mid-reform as IOTL and is this much more cohesive, though naturally less well armed.

The air component of the KNIL was receiving the Martin 139 bomber from September 1936 on out. While this machine was severely outclassed in WWII, at the point of delivery it was pretty good.

Like the other parts of the DEI-defense, the Royal Netherlands Navy had suffered much during the Crisis Years. What does help it though, is that these were the golden years of the submarine-based doctrine. Not enough to stave of the combined might of the Japanese navy, army and airforce no, but it could very well give the Japanese invasion force a bloody nose.

I have some more thought but for that I will need my sources and I'm currently - and happily - on holidays so that will have to wait a few weeks.

Excellent observations, and I look forward to more.

A foreign intervention is a genuine possibility. I think a British is significantly more likely than an American. I have thoughts on how a British intervention could play out.

thus it is very questionable if the Japanese would risk it.

It is one of the less likely, outlier scenarios, sure. It would be a bold initiative.

Don't forget, in WWII the Japanese government didn't know for sure that the US would contest its SLOCS between SEA and the South, but was unable to ignore that possibility.

Oh, I remember. Yet the Japanese even did contemplate doing the bypass of American possessions in making plans in 1941, although that is clearly not the course of action they selected. Many in the Army and some in the Navy preferred that. There might be a reference to this in the US Army green book I mentioned. And there would be many, many differences between a 1936 situation of Japanese- British relations (and British level of armament) and Japanese-American relations (and American level of armament) and what had emerged by OTL in 1941, even though the geographic proximity of British and American territories and the Netherlands East Indies would remain an unchanging factor. The differences were British and American naval rearmament were less advanced, other than verbal complaints over the Manchuria incident and Shanghai incident, with no ongoing China war there was no ongoing tension over that or sanctions or talk of them in 1936. Both countries were more internally consumed with internal agenda items like the abdication crisis, the Palestine revolt for Britain and the Depression recovery, and the Depression recovery and reelection campaign for America. Specific instances of China related tension, the Panay incident (Dec 1937) for the Americans and the Tianjin Blockade (summer 1939) for Britain still lay ahead. Britain was less than a year out from its domestic Peace Ballot and the time of the Oxford Resolves about not Dying for King and Country. The US may have had live political discussion ongoing for the Ludlow Amendment to require a national referendum in addition to war declaration to prosecute wars, and the Nye Committee investigating the arms industry, causes of WWI, and condemning 'merchants of death' was very recent American history causing tightening of American Neutrality Laws by 1935. The bottom-line is that if Naval policy entrepreneurs get it in their heads that this kind of move is a great coup and winning move for their service their nation, and their Emperor, just like the Army Ultra-Patriots who did the Manchuria adventure, they can pluck various "facts" and "factors" for why the risk can succeed, why it must be taken, and why it is a patriotic duty.

Right because the British are stupid enough to trust that they won't change their mind and again their mere presence in the DEI is threat to Singapore and Malaya.

Well yeah, I get that the British were on top of the naval world, and were accustomed to being given a wide berth and could get real sensitive real fast if another power got into their copious personal space. Perhaps more so than powers that had to share continents like the Soviet Union. But Britain had concession areas all around China that and even a Crown Colony in Hong Kong doing millions of pounds sterling in annual business turnover and tolerated Sino-Japanese fighting to happen right up to the border of concession areas...but no further, without getting involved, from June 1937 through December 8th, 1941. From summer '37 British concession areas in Beijing and Tianjin were enveloped. By the end of the year, even more important British concession areas in Shanghai were enveloped by land, but British troops and ships still showed the flag. In November 1938 the Japanese conquered Guangzhou and marched right up to the borders of Hong Kong. Japanese forces proximate to the border of Britain's Hong Kong Crown Colony were involved with vicious fighting with Chinese forces in surrounding Guangdong province for the next two years - with British gun-running to the Chinese! - without Britain and Japan coming to blows. Japan blockaded the Tianjin concession to force the turnover of suspected Chinese assassins in the summer of 1939....still before Britain had the excuse of being distracted by war in Europe, and Britain made a compromise instead of going to war over it, turning the suspects over to get killed.

his on the level of one 10 year old poking another with a ruler and declaring 'see I'm not touching you' and then being surprised when they get smacked in the face...

Hey - I was that kid! The face smacker, not the ruler poker. Actually, I was 14, the other kid was using a ballpoint pen, and it was my fist to the eye-socket.

 

[raharris1973]

But I also accept that third party intervention is a real possibility, and a quite interesting one.

The idea of all the other powers standing aside while Japan lifts the East Indies from the Netherlands may turn out to be fatal miscalculation for Japan. Under pressure from imperial interests and Australia, which perhaps threatens to declare itself an independent republic and seek American protection, Britain under the Baldwin Government declares war on Japan - possibly after Japan disregards an ultimatum to halt and reverse its invasion of the Dutch East Indies, well that will make for an interesting medium-sized war at the tail end of 1936 and early 1937.

Britain would get itself on a war footing and dispatch fleet units to Singapore, and reinforcements of men, ships and aircraft to Australia and the Pacific. Britain's early exertions in war production, mobilization, and deployment would have growing pains, and more men would be immediately be called to the colors of RN, RAF and Army ranks to fill them out to handle needs of the Far East war and ongoing sores like ongoing Arab Revolt in Palestine. Besides continuing its crackdown there, Britain might accelerate its move to the Arab-appeasing policies of 1939 White Paper to substantially restrict and put a 10 year limit on Jewish immigration and land purchases, foreclosing prospects of a Jewish majority there, to make things more quiet.

With prompt action, and the Japanese making their approach through the Dutch East Indies from an east to west axis mainly, the British may be at risk of losing Sarawak and Sabah and Brunei in Borneo, maybe - but not Malaya and Singapore, which the Japanese are unlikely to be able to approach in strength with a combination of land-based AirPower and landing forces in anything like a timely fashion before defenses are prepared and reinforcements arrive. With British assistance, the Dutch should certainly fend off any Japanese attempts to land at Sumatra, and the Dutch and British together could well entirely repulse, or stall, any Japanese invasions of Java. Depending on the tactics and circumstances and locations of battle - proximity to each side's air bases, night fighting versus day fighting, commander skill, luck - each side can suffer some high profile naval losses.

The Americans in all likelihood would not rouse themselves to the defense or direct combat assistance of the British, Australians or Dutch, but they would wish for their victory, and before long suspend exports of raw materials and war material to Japan. The Canadians and probably South Africans through would declare war on the Japanese and send forces to help out their Imperial partners.

The French would not see the Pacific and Far East as their priority, Europe would remain so. They would not "like" participating in a Far East war or devote major national efforts to it. However, by the same token since they want and feel they *need* Britain's strategic backing in European affairs, they would probably not turn down any direct requests for military assistance or use of French facilities in the Far East in Indochina, New Caledonia, Polynesia, by the British Empire, even if this caused a Japanese declaration of war. Even if this incurred damage to the French Empire in the region, earning reciprocal British obligation to France's security in Europe, and not alienating Britain from such ties, would probably be worth it to Paris. So there is a decent chance France would find itself at war with Japan if Britain does. France also would not mind *the Netherlands* owing it favors possibly redeemable in Europe as well.

Overall Japan would be contained early in this war, with a slow rollback, that, without participation of a power like the USSR, is not guaranteed to get Japan out of Manchuria and Korea. Without participation of America, it is not guaranteed to see Japan totally defeated and occupied, merely pushed back from its conquests, some of the China Seas, and Micronesia, after a prolonged submarine campaign.


---Another aspect of any Japanese-Dutch War turning into an Anglo-Japanese War is that it could lead right back to renewed combat in Chinese waters and on Chinese land, with Japan seizing Hong Kong and attacking British forces in the concession areas of China's ports like Shanghai and Tianjin. Chiang might stay neutral if it is appearing to him the British are not offering any revision to treaty port status and seem to be losing, and the Japanese are not spilling over much while they focus on the British, but if the British are offering some reform in the system, and more importantly money and weapons for the long-haul he thinks he can use to reclaim Manchuria, Chiang would become interested in anti-Japanese co-belligerency alongside Britain. Britain would like to make use of the Chinese territory for access to land close enough to bomb the Japanese home islands and inlets in which to hide submarines. It can be a bum costly deal for China though, with the strong Japanese forces in Manchuria and Korea lashing out extensively across northern and eastern China in retaliation for China siding with Britain. But, with this type of coalition forming, Stalin in the USSR may think it a good time to avenge the Tsarist defeat of 1905 and attack Manchuria, Korea, and Sakhalin from the north to demonstrate the new capabilities Socialist Russia has. Lots of possibilities for a different world unfolding here. If the grandest possible anti-Japanese coalition emerges in 1937, the experience of working together there might carry over to a cooperative policy in Europe in Spain by 1938, and in joint support to back Czechoslovakia's territorial integrity that year.

 

[vizzer]

While it should be possible to construct a scenario where neither the UK or the US would intervene, these will not be the most likely, and thus it is very questionable if the Japanese would risk it. Don't forget, in WWII the Japanese government didn't know for sure that the US would contest its SLOCS between SEA and the South, but was unable to ignore that possibility.

The land forces of the KNIL were very much at their lowest point, after years of Great Depression-induced budget cuts. From 1936 budgets increased, though new material was slow to arrive. This does mean that the KNIL isn't caught mid-reform as IOTL and is this much more cohesive, though naturally less well armed.

The air component of the KNIL was receiving the Martin 139 bomber from September 1936 on out. While this machine was severely outclassed in WWII, at the point of delivery it was pretty good.

Like the other parts of the DEI-defense, the Royal Netherlands Navy had suffered much during the Crisis Years. What does help it though, is that these were the golden years of the submarine-based doctrine. Not enough to stave of the combined might of the Japanese navy, army and airforce no, but it could very well give the Japanese invasion force a bloody nose.

I have some more thought but for that I will need my sources and I'm currently - and happily - on holidays so that will have to wait a few weeks.

You can probably ignore the Japanese air force apart from whatever is onboard any carriers. Even then without a constant CAP the Dutch may get an occasional free run at any invasion fleet. Although even with that against warships bombers of the period are likely in effective but may be able to damage/sink transports.

 

[HJ Tulp]

A foreign intervention is a genuine possibility. I think a British is significantly more likely than an American. I have thoughts on how a British intervention could play out.

The economic interests of the UK in the DEI were immense. Lets not forget that Koninklijke Olie and Shell had fused not that long ago. I even remember a source saying that the UK trade with the DEI was larger than the Dutch trade with its own colony was!

It is one of the less likely, outlier scenarios, sure. It would be a bold initiative.

What would trigger this though? Do you have a specific POD in mind? Or a probable casus belli?

. But Britain had concession areas all around China that and even a Crown Colony in Hong Kong doing millions of pounds sterling in annual business turnover and tolerated Sino-Japanese fighting to happen right up to the border of concession areas...but no further, without getting involved, from June 1937 through December 8th, 1941.

I think that this was a case of unintentional 'salami tactics'. If the Japanese had announced they would choke the British out of their Chinese holdings, the respond would be a lot more forceful. In this case Japan is supposed to DoW the Netherlands to gain control of the DEI, so the blinds are off.

There are possibilities of less totallistic objectives though. In fact, one of the greatest fear of the Netherlands was that Japan would perform a coup de main attack on one or more oil ports, like Tarakan or Balikpapan (though Batavia was certainly a feared option as well).

But I also accept that third party intervention is a real possibility, and a quite interesting one.

Agreed.

the British may be at risk of losing Sarawak and Sabah and Brunei in Borneo, maybe - but not Malaya and Singapore, which the Japanese are unlikely to be able to approach in strength with a combination of land-based AirPower and landing forces in anything like a timely fashion before defenses are prepared and reinforcements arrive. With British assistance, the Dutch should certainly fend off any Japanese attempts to land at Sumatra, and the Dutch and British together could well entirely repulse, or stall, any Japanese invasions of Java. Depending on the tactics and circumstances and locations of battle - proximity to each side's air bases, night fighting versus day fighting, commander skill, luck - each side can suffer some high profile naval losses.

For a solid - as solid as possible anyway - analysis we do need to establish a PoD and casus belli though. Is it going to be a prepared attack where a large invasion fleet is assembled or is it going to be a bolt from clear skies? In the first scenario there is more time for diplomatic manouvering and reinforcements on both sides, the second scenario gives more diplomatic outrage though.

There is also the question on how much Japanese forces are available for operations in SEA. What resources have to stay in reserve in case the US/SU/China does involve itself for example?

France also would not mind *the Netherlands* owing it favors possibly redeemable in Europe as well.

A Anglo-Dutch alliance, let alone one involving France as well, in Asia, would make Dutch neutrality in Europe very awkward to say the least.

You can probably ignore the Japanese air force apart from whatever is onboard any carriers

Why would that be?

 

[Ross789]

The economic interests of the UK in the DEI were immense. Lets not forget that Koninklijke Olie and Shell had fused not that long ago. I even remember a source saying that the UK trade with the DEI was larger than the Dutch trade with its own colony was!

If the Japanese were smart they would declare all preexisting deals with foreign businesses would be honoured, and try to encourage further investment. Even dutch ones, if they would sign an armistice.
And all Europeans would be treated very politely.
Of course that assumes a level of control over their soldiers conduct that they didn't have irl.