AHC: Accelerate the Union conquest of Atlanta and march to the sea by a year

[Arnold d.c]

Surely though the reason IOTL that it was relatively rare to see troops from the Army of the Potomac sent west was because the Army of Northern Virginia was still intact and Richmond was still in Confederate hands until the very end of the war and thus those Union troops were still needed in the east. In a timeline where the Union takes Richmond and smashes the AoNV in 1862 though the situation is very different. There will be much less need for Union troops in the east in such a timeline, so why wouldn't Lincoln start sending troops from the Army of the Potomac to the western theater?

Let me turn the question around: when the Union armies in the west were clearly winning in 1862, capturing Nashville, Corinth and Memphis, why did Lincoln not order them to head east and reinforce the Army of the Potomac? It’s simple: the Confederate armies of the west remained a potent force and there were more objectives to accomplish (Vicksburg, Chattanooga, Atlanta, etc.).

For a more modern analogy, should Eisenhower have redirected his troops in France to Italy after Falaise?

The only time I could ever see transfer of troops from the Army of the Potomac to the western Federal armies is if a crisis occurs. The Army of Northern Virginia might have been bloodied and Richmond has fallen, but the rebel army is still standing in North Carolina and has the capability to counterattack. Why not keep the Army of the Potomac fighting on to finish the job? It’s only when an army has accomplished its objectives that elements were redeployed.

As an example of an army that had chunks removed after victory, look at Grant’s Army of the Tennessee post-Vicksburg. With the Mississippi River cleared of Confederate outposts, Grant’s army did not have a mission any longer. Grant sent telegram after telegram to launch a Mobile Campaign, but instead the army assembled for the Siege of Vicksburg was almost disbanded:
- IX Corps returned to Kentucky for the Knoxville Campaign
- XIII Corps went to join the Army of the Gulf, which needed more manpower to defend its territory
- Elements of XVII Corps were detached for operations in Arkansas before being recalled for lifting the Siege of Chattanooga

Or in another case, the Army of the Gulf was practically disbanded after the failure of the Red River Campaign because their troops were better used elsewhere.

 

[raharris1973]

In regards to the early Eastern Theater victories, my opinions are as follows:
1. To me, the most direct benefit to Western Theater lies in draining the Confederacy's reserve pool of coastal units. IOTL, there were considerable reinforcements that were entrained to the Western Theater. Of the top of my head, I can think of Bragg's Pensacola units that joined up for Shiloh, various regiments from coastal states during the Siege of Corinth and a total of 6,886 men from three South Carolina garrison brigades (S.R. Gist, W.H.T. Walker and N.G. Evans) reinforced Joseph Johnston's Army of Relief in 1863.

2. Transfer of units from the Army of Tennessee [Confederate] and Army of Northern Virginia [Confederate] is plausible, especially if the loss of Richmond is fresh. I am more skeptical of a transfer of Confederate regiments from the west to the east in a less dire situation, including a bad defeat. Not even the heavy losses of the Overland Campaign and the Siege of Petersburg induced the Confederates to transfer units from the west to the east amidst the Atlanta Campaign. If Richmond is lost during the Peninsula Campaign, I could imagine that there would no Kentucky Campaign as Confederate soldiers from the western armies are stripped away for a Richmond counterattack.

3. Transfer of units from Army of the Potomac [Union] to the Federal Western armies is quite unlikely, even if there is greater success in the east. Prior to the Siege of Chattanooga, corps-level transfers were incredibly rare. The ones I can think of are the redeployment of IX Corps from Kentucky to Vicksburg to aid Grant's siege of Vicksburg and Grant's transfer of XIII Corps to the Army of the Gulf [Union] after the siege was over. After Chattanooga, large chunks of the Army of the Gulf was transferred to the Shenandoah Valley for Sheridan's Campaign and for the Mobile Campaign. In all cases, large troop transfers were prompted by a crisis of some sort. There were a few Federal regiments that transferred from east to west, including the regiments that surrendered at Harpers' Ferry. At Champion Hill, those men were urged to charge with the taunt, "Go in, Harper's Ferry cowards!"

Thanks for going along with my request to label armies by their side in the conflict.

The Army of Northern Virginia might have been bloodied and Richmond has fallen, but the rebel army is still standing in North Carolina and has the capability to counterattack. Why not keep the Army of the Potomac fighting on to finish the job? It’s only when an army has accomplished its objectives that elements were redeployed.

Yeah - I would think even post Richmond, there would be some clean-up and pacification of south-central, southwestern Virginia to do, fully securing the rail links into Tennessee for example, and fully securing continuity on land with any Federal enclaves on the North Carolina coast. CSA forces in North Carolina would pose the threat of counterattack towards Richmond and Virginia. North Carolina itself is a valuable objective, both individual parts, and the sum of its parts. It's eastern coastal areas and inlets to reinforce the blockade, its far western mountain portion to provide relief and liberation to local populations of reportedly high Unionist sentiment.

As a whole, North Carolina is second only to Virginia as a source of Confederate military manpower, and a huge source of food and draft animals for the CSA forces.

And then, once the conquest of North Carolina is complete, while Atlanta beckons as a target *somewhat* to the west, South Carolina is another fairly logical follow-on target for strategic, political, and symbolic reasons. Taking South Carolina's coast strengthens the blockade and taking its land denies the CSA its rice, cotton, cattle and labor, while politically and symbolically, it crushes the rebellion in the cradle where it started.

So, plenty of objectives for the Army of the Potomac on the eastern seaboard for hundreds of miles, even south of Richmond.

 

[SWS]

If Richmond falls to the combined assault of McClellan and McDowell in the Spring of 1862, and the line of the James River and Central Railroad with it, Goldsboro, N.C., likely becomes McClellan's next primary object. By advancing south on the railroad via Petersburg, Stony Creek, Weldon, and stations on the Wilmington road, he can count on reliable communication with U.S. Navy gunboats/supply steamers and on co-operating columns under Dix and Burnside from Norfolk, Portsmouth, Suffolk, Plymouth, Washington, and New Bern, which would offset any diminishment in the strength of the Army of the Potomac when garrisoning the railroad against Confederate raiders. He can also feint and raid toward Raleigh on the Gaston road, keeping-up the fog of war. There is also an abundance of bacon and forage and the support of Carolinian Unionist "Buffalo" bushwhackers on the line of march, in addition to abandoned plantation residences ripe for pillage, although there would be orders issued against the latter outrage.

That city and its rail junction is the key to occupying eastern North Carolina permanently and denying the Rebellion use of Wilmington's prolific seaport, resulting in the evacuation of Fort Fisher and other harbor defenses. Only Charleston, S.C., would remain open to regular blockade-running traffic from Nassau and Bermuda. Operating westward against Raleigh and Greensboro would sever Danville's remaining Piedmont communications with the lower South. Operating southwestward against Fayetteville and the line of Cape Fear would eliminate the Confederacy's important remaining arsenal, although the machinery would likely be removed to Columbia, and open an avenue into the heart of South Carolina via Florence and Camden across the semi-desert Pee Dee Valley. It is up to Banks and Frémont and other U.S. elements to capture Lynchburg and Southwest Virginia's lead and saltworks, securing the rail-route into East Tennessee, permitting inter-theater Federal co-operation in occupying the upper Tennessee Valley, an object dear to Lincoln's heart. From East Tennessee, U.S. Cavalry and Unionist partisans can raid against Lee's rear.

The only problem being Lee and Army of Northern Virginia lying in repose at Burkeville Junction, prepared to counter and strike in either direction. And McClellan will no doubt either await Confederate capitulation or the passing of the midsummer disease season. Nonetheless, Confederate communications with the Old North State are impaired somewhat by the non-completion of the Piedmont Railroad's Danville-Greensboro connection.

The scene of Confederate re-concentration.

 

[raharris1973]

There is also an abundance of bacon and forage and the support of Carolinian Unionist "Buffalo" bushwhackers on the line of march,

That east-central portion of North Carolina on the tidewater seems *least* likely to have local populations of white Unionists to serve as pro-Union bushwhackers. Or is your "Buffalo" adjective meant to imply black bushwhackers, free blacks, runaway and mutinous slaves?