Antietam

MikeyB

Corporal
Joined
Sep 13, 2018
Is there any reasonable Antietam scenario where the war ends shortly after a Union victory? So for instance, if Mac attacks again on the 18th and Lee loses half his command or more and barely makes it back into Virginia, or even worse. If the ANV is effectively destroyed, does Richmond even contemplate surrender, or are there just too many other CSA military assets still in good order that there is no way this happens?
 

jackt62

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Jul 28, 2015
Location
New York City
If the ANV is effectively destroyed, the game in the east is probably over. And by "destroyed" we are saying that the army ceases to exist as an effective fighting force, either by mass surrender or by total decimation by casualties. That was the goal of Lincoln and the administration from Day 1 in its instructions to McClellan, Burnside, Hooker, Meade. But none of those commanders came close to that goal; Grant did achieve the total surrender of the ANV, but even he was unable to destroy that army in the field. It took a relentless and continuous campaign that brought to bear the increasing industrial might of the North, while diminishing the manpower resources of the South. Regarding Antietam, there were options that McClellan could have applied to possibly achieve a tactical victory by committing additional forces to the September 17th assaults and effecting greater coordination or by resuming the attack on the 18th. However, even if the AOTP achieved a greater success than it actually did, I don't see a reasonable scenario in either of those cases for an overwhelming defeat of the ANV.
 

Carronade

Captain
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Aug 4, 2011
Location
Pennsylvania
Jeff Davis wouldn't contemplate surrender in 1865; even after he evacuated Richmond he was looking for ways to carry on the war. In September 1862, most of the Confederacy had not yet been touched by war. Confederate armies were in the field and indeed on the offensive. It's hard to see a short war or easy victory whatever happens in Virginia.
 

67th Tigers

1st Lieutenant
Joined
Nov 10, 2006
An attack on the 18th was unlikely to be successful. One on the 19th would have, but Lee was gone.

I think more interesting is a variant campaign. McClellan moved Burnside's and Sumner's wings to Harper's Ferry and was preparing to cross and cut Lee off. Halleck intervened and prevented it. Had McClellan been unfettered he would have cut across Lee's supply line and compelled Lee to attack him. It might have resulted in Lee's destruction.
 

Andy Cardinal

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Location
Ohio
An attack on the 18th was unlikely to be successful. One on the 19th would have, but Lee was gone.

I think more interesting is a variant campaign. McClellan moved Burnside's and Sumner's wings to Harper's Ferry and was preparing to cross and cut Lee off. Halleck intervened and prevented it. Had McClellan been unfettered he would have cut across Lee's supply line and compelled Lee to attack him. It might have resulted in Lee's destruction.
Can I see more about Halleck's intervention please?
 

Mango Hill

Corporal
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Jul 23, 2020
Halleck didn't intervene. McClellan proposed two options:

1. Head towards Winchester and hopefully engage Lee there
2. Advance from Harpers Ferry keeping the AOP between Washington and the ANV.

McClellan initially proposed option no. 1 but, if Lee decided to retreat to Staunton, McClellan was stuck as he could not go after Lee due to a bushel load of reasons, with the main one being he could not supply the AOP beyond Winchester. This was McClellan's own assessment.

So, after many delays due to lack of uniforms, shoes, horses, etc. McClellan chose option no. 2 (Lincoln's favorite) and crossed into Virginia via pontoon bridges at Berlin and Harpers Ferry by the end of October. By the time McClellan was dismissed as commander of the AOP he's army was located in the vicinity of Winchester, Waterloo - Rappahannock River, New Baltimore, Gainesville, Thoroughfare Gap, Between Manassas Junction and Warrenton Junction with Pleasanton across the Rappahannock River.

Back to Antietam on the 18th. McClellan had stated in one of his reports on the Battle of Antietam that if Miles had not surrendered, and (somehow) escaped the trap set by Jackson with the assistance of Couch's division coming to the rescue, his 12,000 troops would have made made difference and Lee would have been destroyed. Of course, typically of McClellan, in this report he conveniently leaves out that Couch's Division of about 5,000 and Humphrey's Corp of about 6,000 were available that morning to be used in the proposed imaginary attack. He conveniently throws miles under the bus (and with reason) as a cover for the criticisms of his inaction on the 18th.

OK. Now that I got that off my chest the answer to the OP is that you can never expect that McClellan would destroy Lee because that was never his intention. McClellan was scared to death of Lee and always expected that Lee was hiding this huge force just ready to pounce and destroy him.
 

67th Tigers

1st Lieutenant
Joined
Nov 10, 2006
I have a long post about this. However:

McClellan has moved 1st, 9th, 2nd and 12th Corps to Harper's Ferry by the 23rd September with the main body of cavalry. He left 5th and 6th Corps, plus cavalry detachments, to watch the fords at Shepherdstown and Williamsport. Sumner has been ordered to construct pontoon bridges, and McClellan has contacted the President of the Chesapeake and Ohio Railroad to rebuild the bridge. Halleck is asked to authorise the expense. The next day he gives a non-committal reply, and McClellan pushes on his project to cut Lee off. On the 26th Halleck finally understands McClellan's intent to cross the Potomac, and essentially forbids it. This ends the Maryland campaign.

Halleck asked for McClellan to suggest a plan on 6th October. McClellan suggested going straight at Jackson, now at Winchester (incidently cutting Longstreet off). If Jackson retreated to Staunton, then a new line would be adopted aiming at Richmond. This time it will be Lincoln that writes denying permission for McClellan to take the offensive, and this doesn't arrive until 16th October.
 

Saphroneth

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Feb 18, 2017
OK. Now that I got that off my chest the answer to the OP is that you can never expect that McClellan would destroy Lee because that was never his intention. McClellan was scared to death of Lee and always expected that Lee was hiding this huge force just ready to pounce and destroy him.
This doesn't really make sense of McClellan's actions at Antietam, though. I'd agree that McClellan doesn't have a hard lock on exactly how many men Lee has, but as of late on the 16th McClellan has committed 1st, 12th and 9th Corps to attack and will send 2nd Corps over during the night. This means he's committed all but two divisions on the field to attack (Sykes and Richardson; he releases Richardson back to 2nd Corps when Morell arrives).

McClellan's concept of operations is to hit Lee from the north with a heavy attack and send a less powerful but still corps strength at him from the south, in an attempt to hit Lee and also cut off his retreat. The fact that it collapsed in a haze of "friction" (in the Clausewitzian sense) doesn't mean the concept of operation didn't exist in the first place, and what it means is that McClellan is keeping back two divisions that aren't committed to the attack.
This is an attempt to destroy that portion of Lee's army which is north of the Potomac.

As of the early afternoon, it is self-evident that the attack from the north has not been successful, but Franklin's five fresh brigades are able to keep on pressure simply by existing - they are preventing Lee's remaining force from turning on Burnside. At this point the thing McClellan could do to minimize his exposure if he fears Lee has a strong remaining force is to cancel Burnside's attack - this would create a situation where Lee can't direct his whole remaining force either north or south, since there is a threat from both directions.
Instead what McClellan does is to check on Burnside to try and speed him up, and order two of his last three uncommitted brigades north to join Franklin for an attack; Sykes' division is to be ready to advance on Burnside's flank.
This is an attempt to deliver a strong blow.

Only once Burnside collapses does McClellan stop making preparations to try and hit Lee further on the 17th, and this is because at this point almost McClellan's entire army is spent. He has a total of six fresh brigades in the north (Franklin's five plus one flank guard from 1st Corps), four and a half in the centre (Morell's three plus one from Sykes, along with Warren's tiny two-regiment brigade) and none in the south where Burnside has given way; the remaining thirty-three brigades on the field are either tired out from fighting or (in the overwhelming majority of cases) have been repulsed or routed.

McClellan does not know how strong Lee is; what he does know is that Lee has fended off attacks by approximately 60,000 men and seems to keep bringing up new reserves. Consequently McClellan opts to wait to attack when conditions are more favourable.

This is of a piece with his movements to South Mountain (which involve a fast movement from Frederick to hit at places where Lee is vulnerable, disregarding the possibility of another Confederate force south of the Potomac that might try and strike at Washington).

On the 18th McClellan seriously considers attack, but a number of factors (like the still-shattered state of 1st and 2nd Corps, Burnside insisting that he needs to be reinforced urgently, a serious lack of artillery ammunition, and the exhausted state of Humphreys' division when it arrives from Washington) mean that the attack is postponed to the 19th. On the 19th McClellan of course attacks early in the morning but the Confederates evacuated overnight.


Antietam does not look like McClellan never intended to destroy Lee's army. It looks like McClellan attacked hard when it looked like there was a reasonable chance of killing or mauling Lee's army based on the information he could know, and that when he stopped attacking it was because he'd essentially run out of reserves - perhaps he could have made one more two-brigade attack without risking the destruction of his army, but Lee has three brigades that he hasn't even fired a shot with.




This isn't to say that Antietam was a battle that couldn't have come out a success - it's just that what needs to happen is a bit more coordination in getting over the Lower Bridge. A good way for this to happen would be for Reno to survive, since it seems that the loss of Reno harmed the articulation of 9th Corps and led to much of the delay. Have that and you have 9th Corps getting over the bridge hours earlier, which offers at least the possibility of the 9th Corps attack going through well before AP Hill arrives - combine that with the two brigades of Morell (historically sent) and the five brigades of Franklin making an attack at the same time and that could overpressure the Confederate lines.

Of course, it's not like cases where 43.5 brigades broke 39 brigades exactly abound in the Civil War...
 

Mango Hill

Corporal
Joined
Jul 23, 2020
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Mango Hill

Corporal
Joined
Jul 23, 2020
I have a long post about this. However:

McClellan has moved 1st, 9th, 2nd and 12th Corps to Harper's Ferry by the 23rd September with the main body of cavalry. He left 5th and 6th Corps, plus cavalry detachments, to watch the fords at Shepherdstown and Williamsport. Sumner has been ordered to construct pontoon bridges, and McClellan has contacted the President of the Chesapeake and Ohio Railroad to rebuild the bridge. Halleck is asked to authorise the expense. The next day he gives a non-committal reply, and McClellan pushes on his project to cut Lee off. On the 26th Halleck finally understands McClellan's intent to cross the Potomac, and essentially forbids it. This ends the Maryland campaign.

Halleck asked for McClellan to suggest a plan on 6th October. McClellan suggested going straight at Jackson, now at Winchester (incidently cutting Longstreet off). If Jackson retreated to Staunton, then a new line would be adopted aiming at Richmond. This time it will be Lincoln that writes denying permission for McClellan to take the offensive, and this doesn't arrive until 16th October.

McClellan was not going to be cutting anybody off at Winchester if he wanted his army to survive longer than ten days. After Lee crossed the Potomac he had the RR between Harper's Ferry and Winchester destroyed. McClellan not only would have had to wait the 3 - 4 weeks for the RR across Harpers Ferry to be rebuilt while restoring the destroyed branch of the HF - Winchester and the 30 miles of destroyed B & O track. That would have been a good deed but would not have led anywhere. McClellan's other options were to go the route he took which would have led him to Gordonsville, but that was a risky one since the AOTP would have had to rely on the Orange & Alexandria RR for supplies (a Third Bull Run). The other options were his favorite one down the Peninsula (which Lincoln would never approve) or the more familiar Fredericksburg - Rappahannock line.
 

Saphroneth

Captain
Joined
Feb 18, 2017
McClellan was not going to be cutting anybody off at Winchester if he wanted his army to survive longer than ten days. After Lee crossed the Potomac he had the RR between Harper's Ferry and Winchester destroyed. McClellan not only would have had to wait the 3 - 4 weeks for the RR across Harpers Ferry to be rebuilt while restoring the destroyed branch of the HF - Winchester and the 30 miles of destroyed B & O track. That would have been a good deed but would not have led anywhere. McClellan's other options were to go the route he took which would have led him to Gordonsville, but that was a risky one since the AOTP would have had to rely on the Orange & Alexandria RR for supplies (a Third Bull Run). The other options were his favorite one down the Peninsula (which Lincoln would never approve) or the more familiar Fredericksburg - Rappahannock line.
You can supply about 20-25 miles away from a rail terminus - if you have the rail line to Harpers Ferry (i.e. over the Monocacy) intact and you have a bridge at Harpers Ferry you can operate about as far as Winchester. The problem is that without the Monocacy bridge repaired and without the HF bridge in place then to get to Winchester you're operating twice as far from a rail terminus as you can supply.

The repair of the Winchester-to-HF rail line isn't necessary to operate at Winchester, and if Lee retreats south - well, then you do what McClellan said he would, and move south as well. (The reason to strike at Winchester is that even if it doesn't work you make sure Lee can't then invade the North at short notice.)
 

Mango Hill

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You can supply about 20-25 miles away from a rail terminus - if you have the rail line to Harpers Ferry (i.e. over the Monocacy) intact and you have a bridge at Harpers Ferry you can operate about as far as Winchester. The problem is that without the Monocacy bridge repaired and without the HF bridge in place then to get to Winchester you're operating twice as far from a rail terminus as you can supply.

The repair of the Winchester-to-HF rail line isn't necessary to operate at Winchester, and if Lee retreats south - well, then you do what McClellan said he would, and move south as well. (The reason to strike at Winchester is that even if it doesn't work you make sure Lee can't then invade the North at short notice.)

And a great move it was. Going by what @67thTigers proposed (partly incorrect, IMO) McClellan couldn't have cut Jackson off so soon after Antietam (if I understand @67thTigers correctly) because of supply issues and Lee's army was still around the Bunker Hill - Winchester area. After the AOTP crossed the Potomac in force on October 26th Lee decided on October 28th to leave Jackson in the area of Berryville - Charleston west of the Shenandoah River and close by Winchester. Lee then moved with Longstreet to Culpeper. Lee had predicted this move as this illustration from DS Freeman's Lee shows:

1598492124035.png

McClellan then proceeded to direct what can only be described as a brilliant advance which did (for practical purposes) cut Jackson off from the main force at Culpeper by capturing all the gaps in the Blue ridge Mts. down to Thornton's Gap. The only gap left available to Jackson that was closest to his position was the one used by Longstreet, which was Swift Run Gap. McClellan had effectively cut off the two main bodies from each other and, what's even more brilliant, at such a distance of separation, they could not quickly support each other. So, for better or for worse, delay served the AOTP well. Lee then made preparations to move from Culpeper to Gordonsville and await the arrival of Jackson if McClellan moved on Longstreet. IMO, if Little Mac had not been replaced by Burnside this would have been the route of attack. Considering that Fredericksburg was a disaster a move towards Gordonsville couldn't have had a worse outcome. McClellan would have forced Lee to battle there minus Jackson and outnumbered by about 3 to 1. My one concern is, as Meade said, the Orange & Alexandria RR couldn't have supplied the AOTP that far south.
 

Saphroneth

Captain
Joined
Feb 18, 2017
My one concern is, as Meade said, the Orange & Alexandria RR couldn't have supplied the AOTP that far south.
I've been turning this problem over for a while, and my suspicion is that what McClellan would have done is to cross the Rapidan in force before moving east to the Fredericksburg area for supply (from Port Royal and the RF&P). Depending on Lee's reaction, McClellan could have left a couple of corps in the Orange area (since that would be much easier for the O&A to supply medium-term) but the end-state for the Union army is that there's a large Union force in supply south of the Rapidan; they can then march on Richmond from the north, or hook around the eastern flank, depending on whether Jackson has arrived yet.
If Lee retreats west from Gordonsville then there's nothing between McClellan and Richmond; if Lee retreats east from Gordonsville then a couple of corps in the Orange area can cut Jackson off from Longstreet. Lee may have a countermove but I haven't been able to determine a good one.
 

Saphroneth

Captain
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Feb 18, 2017
Going by what @67thTigers proposed (partly incorrect, IMO) McClellan couldn't have cut Jackson off so soon after Antietam (if I understand @67thTigers correctly) because of supply issues and Lee's army was still around the Bunker Hill - Winchester area.
Just a quick point here - my understanding is that McClellan was looking to cut off Longstreet who was further north around Martinsburg. This would compel Jackson to fight for Winchester.
 

Saphroneth

Captain
Joined
Feb 18, 2017
It occurs to me that there's the possibility of a comprehensive defeat for Lee at Antietam or otherwise in the Maryland campaign if Lee makes a mistake.

I was thinking a bit over whether there'd still be an Antietam if Harpers Ferry held out for a bit longer (resulting in the capture of McLaws' wing) but I don't think so because I think under those circumstances Lee would evacuate Maryland ASAP - any hope of continuing north would be dashed. However I think there's a possibility of Lee being trapped if things work out a bit differently - specifically:

AP Hill's entire force goes to Antietam rather than 5/6 brigades, and does so earlier than historically by an hour or two. (The result of Lee's order being premptory and not specifying that AP Hill should leave a brigade at HF).
Franklin sees this, and (because he feels like he screwed up in not pursuing hard after Crampton's Gap) when McClellan sends for his corps he instead sends Couch and follows AP Hill.
Back at Antietam, McClellan finds himself having to commit Morell and Couch to shore up his line in the north. He orders Burnside to keep going for now.
AP Hill outpaces Franklin and arrives on the field an hour or two earlier than historically, and contributes to pushing 9th Corps back - possibly in less disarray, possibly more.
Franklin's corps seals off the south side of the Shepherdstown fords.

Perhaps Lee could get out of this with a breakout attempt to the north, or even to the south (near the ironworks), but there's definitely the scope for a complete loss of the AoNV.

Which rather explains why AP Hill left a brigade behind...
 

Mango Hill

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Jul 23, 2020
I've been turning this problem over for a while, and my suspicion is that what McClellan would have done is to cross the Rapidan in force before moving east to the Fredericksburg area for supply (from Port Royal and the RF&P). Depending on Lee's reaction, McClellan could have left a couple of corps in the Orange area (since that would be much easier for the O&A to supply medium-term) but the end-state for the Union army is that there's a large Union force in supply south of the Rapidan; they can then march on Richmond from the north, or hook around the eastern flank, depending on whether Jackson has arrived yet.
If Lee retreats west from Gordonsville then there's nothing between McClellan and Richmond; if Lee retreats east from Gordonsville then a couple of corps in the Orange area can cut Jackson off from Longstreet. Lee may have a countermove but I haven't been able to determine a good one.

I think McClellan declared in one of his reports that he was positioned to go either north, west or south form the position he occupied before being relieved of command by Burnside. According to Mac the direction would have been determined by Lee's actions. Mac already had Pleasanton's cavalry across the Rappahannock and I believe there's a mention of a skirmish around Culpepper Courthouse in which some of Longstreet's forces were repelled. Taking a cue of how proud Mac was of his conduct of the campaign I believe he would have seeked a battle with Lee before Jackson could have joined him as long as it didn't take his army beyond Gordonsville. According to Pendleton's Memoirs Lee was planning to make his stand at Robertson's River, which is about 15 miles SE of Culpepper Courthouse. This would have made a battle possible, if not probable. One thing that has to be taken into consideration is Mac propensity to over estimate the force he's facing - thus causing him to panic - and begin demanding reinforcements before beginning the battle. Pendleton continues in his observations that Burnside blundered by making Richmond the target, thus moving his base to Fredericksburg. What Burnside should have done is to concentrate on Lee. Of course this is hindsight and Pendleton may not have been aware of the supply issues of relying on a single railroad for supplies. Pendleton was used to relying on long supply lines via road a long way from a major supply hub; such as Staunton to Winchester. Of course the AONV was a much leaner outfit than the AOTP so required less supplies.
 

Mango Hill

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Jul 23, 2020
It occurs to me that there's the possibility of a comprehensive defeat for Lee at Antietam or otherwise in the Maryland campaign if Lee makes a mistake.

I think he did make a mistake. Lee should have listened to Longstreet and retreated back to Virginia after the capture of HF.
 

67th Tigers

1st Lieutenant
Joined
Nov 10, 2006
I think McClellan declared in one of his reports that he was positioned to go either north, west or south form the position he occupied before being relieved of command by Burnside. According to Mac the direction would have been determined by Lee's actions. Mac already had Pleasanton's cavalry across the Rappahannock and I believe there's a mention of a skirmish around Culpepper Courthouse in which some of Longstreet's forces were repelled.

Two of Burnside's 9th Corps divisions held bridgeheads over the river on the far bank, supporting the cavalry. Lee tasked Stuart and McLaws to drive in the cavalry, and they stopped when they found entrenched infantry south of the river. When Burnside assumed command he withdrew these divisions.

I think Saph has some good maps which he can post.
 

John S. Carter

Sergeant Major
Joined
Mar 15, 2017
Halleck didn't intervene. McClellan proposed two options:

1. Head towards Winchester and hopefully engage Lee there
2. Advance from Harpers Ferry keeping the AOP between Washington and the ANV.

McClellan initially proposed option no. 1 but, if Lee decided to retreat to Staunton, McClellan was stuck as he could not go after Lee due to a bushel load of reasons, with the main one being he could not supply the AOP beyond Winchester. This was McClellan's own assessment.

So, after many delays due to lack of uniforms, shoes, horses, etc. McClellan chose option no. 2 (Lincoln's favorite) and crossed into Virginia via pontoon bridges at Berlin and Harpers Ferry by the end of October. By the time McClellan was dismissed as commander of the AOP he's army was located in the vicinity of Winchester, Waterloo - Rappahannock River, New Baltimore, Gainesville, Thoroughfare Gap, Between Manassas Junction and Warrenton Junction with Pleasanton across the Rappahannock River.

Back to Antietam on the 18th. McClellan had stated in one of his reports on the Battle of Antietam that if Miles had not surrendered, and (somehow) escaped the trap set by Jackson with the assistance of Couch's division coming to the rescue, his 12,000 troops would have made made difference and Lee would have been destroyed. Of course, typically of McClellan, in this report he conveniently leaves out that Couch's Division of about 5,000 and Humphrey's Corp of about 6,000 were available that morning to be used in the proposed imaginary attack. He conveniently throws miles under the bus (and with reason) as a cover for the criticisms of his inaction on the 18th.

OK. Now that I got that off my chest the answer to the OP is that you can never expect that McClellan would destroy Lee because that was never his intention. McClellan was scared to death of Lee and always expected that Lee was hiding this huge force just ready to pounce and destroy him.
What was the mental and physical condition of McClellan's force after the battle ? Beauregard could have walked into Washington following the humiliation of Union forces at first Manassas /Bull Run .but did anyone esp Davis or his cabinet question why he did not follow McDowell into the Capital ?Then the same with Meade at that other misopportunity battle.The reason why George is so infamous is because he is remember for his campaign against Richmond ,that was a real success.Then what happened with the second chance ?Every general has his one battle be he Alexander,Julius,Lee,or even Grant.But to be successful one does not continue not to learn from defeat.
 
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