Italy have clearly been dragged into the Spanish-American War somehow- note the Spanish army unit in Charlotteville and the Spanish warship off Charleston, plus the date. You'd need to have some Italian colonies somewhere in the Western Hemisphere, surely- or the war could have set off...
I did post an idea once where Britain adopts a strange variant of a "two Chinas" policy where the PRC is recognised as the legitimate government of the Mainland, but the ROC is recognised as the legitimate government of Taiwan and the successor of the Qing Empire. Therefore, Hong Kong is leased...
That took a fairly long time, though- they last fought against each other in 1815, and first allied 102 years later- and even then WW1 was not necessarily a permanent alliance and they were planning defence against each other in the late 20s and early 30s.
Britain and Israel might count- from fighting Haganah in 1948 to Suez in 1956.
Do forced changes of sides count? I'm surprised no-one has mentioned Italy in WW2 yet, and there's also Finland from Continuation War to Lapland War.
The Balkan Wars probably set the record (in modern times at...
Re British jets: The planned but unbuilt Comet 5 did have engines under the wings (I think), despite the fact that low-bypass turbofans such as the Conway did fit in the wings of some aircraft (Victor B2). Later British jetliners had their engines mounted on the tail- I think the BAe 146 was the...
I didn't say Britain would remain at Suez, I said East of Suez- in 1967 IOTL the British government withdrew its troops from most of the bases east of Suez. These were in Malaysia, Singapore and most importantly Aden. ITTL a continued British presence in the Middle East could be a way to...
While it wouldn't be an American fortress to the same extent, the Americans might well end up propping up say Lebanon, Syria or Egypt.
Other possible implications:
Might Britain remain East of Suez for longer ITTL?
Would there be a resurgence of, if not anti-Semitism, then distrust of Jews in...
I could see a "UN navy" happening, and possibly an air force (only transport aircraft). Many countries that contribute troops to the UN aren't really able to project power, so possibly you could have the UN own and operate a fleet of amphibious landing ships for both humanitarian operations and...
Either that or use a country that didn't sign the treaty. The only major powers that didn't were the US and China. Some South American countries also didn't (including Bolivia which actually tried to issue letters of marque in 1879), and the only Asian countries to sign were the Ottoman Empire...
IIRC the WW1 German commerce raiders were also state warships. I have heard stories about the Goodyear blimp being issued a letter of marque in WW2, but that may be apocryphal.
Salazar did lease bases in the Azores to the Allies IOTL- the ports of Horta and Ponta Delgada and the Lagens and Santana airfields. The agreement was signed in August 1943, and Coastal Command ASW operations out of Lagens began in October. The Azores were also used as a refuelling point for...