Porter Alexander's Assessment of Lee's Decision to Fight

What good would a tactical victory have done?

For starters, if the AOTP was able to destroy a good part of the ANV by causing its capture or utter rout, it would have done immeasurable damage to the ability of the ANV to continue its offensive capabilities. Lincoln was consistently urging his commanders to damage and pursue the enemy to the extent that its effectiveness was ended or diminished, an action that did not happen at Antietam, and which allowed the ANV to regroup across the Potomac, thereby remaining a powerful military force to be reckoned with.
 
For starters, if the AOTP was able to destroy a good part of the ANV by causing its capture or utter rout, it would have done immeasurable damage to the ability of the ANV to continue its offensive capabilities. Lincoln was consistently urging his commanders to damage and pursue the enemy to the extent that its effectiveness was ended or diminished, an action that did not happen at Antietam, and which allowed the ANV to regroup across the Potomac, thereby remaining a powerful military force to be reckoned with.
There was no real concern for the ANV’s survival.
 
It also explains why McClellan delayed in releasing Sumner to cross the Antietam.
As I understand the battle, Sumner's attack order to General Sedgwick caused his division to be badly handled at the West Woods. This experience subsequently led Sumner to advise McClellan not to commit any further reserves to the battle, a reaction which probably cost the AOTP a real tactical victory, rather than a draw, at Antietam.
What good would a tactical victory have done?

It takes a lot of work to see the possibilities of Sumner's attack and how it went so badly, IMHO.

For the Union, you have one of Sumner's divisions wandering off and bad lower-level staff work messing up the co-ordination of the movement. Sumner is leading from the front -- which often is a key to good results but in this instance leads to a disaster because he is not physically present to straighten out the errors concerning the rest of his troops in the rear. French's division wanders off to the left instead of following Sedgwick's division as intended (the poor staff-work). Then, as Sedgwick's lead brigade neared the woods, bad communications causes a split in the front of Gorman's brigade (34th NY goes left, the others go right) -- Gorman's weakened brigade gets thrashed by Early as a result. McLaws (sent by Lee) and artillery support comes up and attack.

Sumners plan was to have Sedgwick drive into the NE part of the West Woods with French following closely to cover his left rear. Then these two divisions would wheel left, clear the West Woods and drive on Sharpsburg. The rest of Sumner's Corps (Richardson's division) is to follow to support and extend this attack.

If that attack works, the West Woods is cleared at about 10-11 AM or so. French is not over near the Bloody Lane getting shot into the ground, he is pressing down from the Dunker Church toward Sharpsburg, outflanking the Bloody Lane. Richardson has followed along and is available as a reserve for Sumner to deploy as needed to cover his right rear or to strengthen the advance on Sharpsburg. McClellan, if he sees this success, probably commits other forces more quickly because the opportunity to crush Lee and the ANV will be obvious.

That's a big change in what actually happened, but it is what Sumner was aiming at. Union mistakes and ineptness played a big part in fouling it up. So did Lee's timely dispatch of McLaws and others to save the day. But if French and Richardson are following up as they should, if Sumner's staff and division commanders acted better, if McLaws arrives a little later ... then Sumner's attack might have had a huge impact.
 
Sumners plan was to have Sedgwick drive into the NE part of the West Woods with French following closely to cover his left rear. Then these two divisions would wheel left, clear the West Woods and drive on Sharpsburg. The rest of Sumner's Corps (Richardson's division) is to follow to support and extend this attack.

If that attack works, the West Woods is cleared at about 10-11 AM or so. French is not over near the Bloody Lane getting shot into the ground, he is pressing down from the Dunker Church toward Sharpsburg, outflanking the Bloody Lane.
French’s division couldn’t have supported the left-rear of Sedgwick’s division, because Greene’s division was on the left of Sedgwick’s division. When Sumner arrives near the action, Greene’s division is sitting on/behind the hill next to the Dunker Church, and Sumner orders Sedgwick’s division to enter the woods on Greene’s immediate right. When French’s division arrives 30 minutes later, he thinks Greene’s division is Sedgwick’s division, and attacks on its immediate left.
“The Antietam Creek was forded by the division, marching in three columns of brigades, Max Weber on the left, the new regiments in the center, and Kimball's brigade on the right. When my left flank had cleared the ford a mile, the division faced to the left, forming three lines of battle adjacent to and contiguous with Sedgwick's, and immediately moved to the front.”

http://antietam.aotw.org/exhibit.php?exhibit_id=54
F9D4073E-76BA-4165-BF5F-C0511BD76A9E.jpeg

Seems to me French did exactly what he thought he was supposed to do.

In my opinion, the Union failures in the second phase of the battle were entirely the fault of Sumner and McClellan. Sumner for not taking the time to send a line of skirmishers into the West Woods ahead of Sedgwick’s division to alert them of any confederates that might be there. McClellan for not sending Richardson’s division immediately across the creek with French’s division. If Richardson’s division arrives at the Sunken Road before R.H. Anderson’s division of confederates, then the federals easily take control of the Sunken Road, and then it might have been R.H. Anderson’s division getting slaughtered by Richardson’s division, instead of the other way around.
 
...
Seems to me French did exactly what he thought he was supposed to do.
...

But not what his commander wanted him to do.

I have no issue with acknowledging that mistakes were made here. There is a severe issue with Sumner-his-staff-his division commanders-their staffs in evidence. In a well-oiled organization what happened here would not happen -- because the commanders and staffs would self-correct. If they needed to communicate with each other, they would. If they needed to contact Sumner, they would. You would not see commanders heading off in the wrong direction because they "thought" they should. These types of actions are supposed to happen without the Corps commander baby-sitting everything personally.

If Sumner had stayed behind, he might have caught this in progress and straightened it out (although that would not have prevented Sedgwick's lead brigade from splitting and leaving a gap, so Sedgwick would have trouble anyway). As an old Dragoon, Sumner was leading from the front, placing himself where he could exert immediate control of the crucial point (or so he thought). This is a normal tactical doctrine for aggressive armies, taught in schools and practiced by Napoleon's generals as well as the Wehrmacht's armies in WWII and often leads to great tactical success (also a reason so many of those generals became combat casualties).

Sumner's plan is also based on a fluid situation and he doesn't really have the details of where Greene is or the rest of the Union flank units. He is riding forward to figure it out as he moves. Things go badly, his Corps lurches into action and drifts out of control. As all that happens, Lee's reinforcements arrive and counter-attack with Early, the situation goes downhill quickly.

But if Sumner's men had worked together to execute his orders, this situation would be much better for the Union. (Example: Sumner's or Sedgwick's staff could have left an aide to tell French which way they went and French could have dispatched an aide to find Sedgwick or Sumner when he wasn't sure.) If Sumner,Sedgwick and French are in communication, they can discover where Greene is and act with Greene to handle the situation effectively. If that is going on, Sumner's attack works much better and French is available to counter McLaw's attack. By being up with Sedgwick, Sumner gets caught in the fight and can no longer function as a Corps commander because he has no contact with Richardson or French.

It clearly did not happen that way and Sumner got clubbed in the West Woods from three sides. That doesn't mean Sumner was an idiot or that slight changes couldn't make this work better (hard to make it work worse :smile:).
 
Alexander's military credentials before the Battle of Antietam (9/1862) :

1857 - graduated from West Point
1858 - was sent to Utah Expedition but did not make it before it was over
1858-1861 - teaching Signal Corps at West Point
1861-11/1862 - Chief of Ordinance i.e. supply master for Artillery

Not.That.Much.
 
It takes a lot of work to see the possibilities of Sumner's attack and how it went so badly, IMHO.

For the Union, you have one of Sumner's divisions wandering off and bad lower-level staff work messing up the co-ordination of the movement. Sumner is leading from the front -- which often is a key to good results but in this instance leads to a disaster because he is not physically present to straighten out the errors concerning the rest of his troops in the rear. French's division wanders off to the left instead of following Sedgwick's division as intended (the poor staff-work). Then, as Sedgwick's lead brigade neared the woods, bad communications causes a split in the front of Gorman's brigade (34th NY goes left, the others go right) -- Gorman's weakened brigade gets thrashed by Early as a result. McLaws (sent by Lee) and artillery support comes up and attack.

I generally agree with this assessment. However I agree with @Wesley P Ellington that French believed he was doing as ordered. My question is did Sumner realize Greene's division was there, or did he base his plan on the belief that French would move into the area that was in reality occupied by Greene's troops?

Sumner's plan is also based on a fluid situation
Definitely true.... It's hard looking back at without coloring our opinions based on what we know after the fact. If I understand it correctly, when Sumner first approached the area there was no organized defense in the West Woods. Jubal Early was desperately trying cobble together a defense and praying for reinforcements to arrive.

The 125th Pennsylvania was engaged south and east of the Dunker Church. Sumner visited the Pennsylvanians before Sedgwick's division entered the woods.

Sumner believed he had a good grasp of the situation, but in reality, by the time Sedgwick's men entered the woods the reinforcements Early was waiting for had arrived. Speaking in the most simple terms, they arrived at exactly the right place at exactly the right time.

I believe this was the biggest moment (of a few) that the battle hung in the balance.

Maybe (probably) Sumner should have had skirmishers out in front, but would that have made a huge difference in the outcome given the way Sedgwick's three brigades were deployed?

If that attack works, the West Woods is cleared at about 10-11 AM or so. French is not over near the Bloody Lane getting shot into the ground, he is pressing down from the Dunker Church toward Sharpsburg, outflanking the Bloody Lane. Richardson has followed along and is available as a reserve for Sumner to deploy as needed to cover his right rear or to strengthen the advance on Sharpsburg. McClellan, if he sees this success, probably commits other forces more quickly because the opportunity to crush Lee and the ANV will be obvious.

Agreed. As I've quoted before on a different thread (quoting Ethan Rafuse), if Sedgwick had been 15 minutes sooner or 15 minutes later it would have made a big difference.
 
Alexander's military credentials before the Battle of Antietam (9/1862) :

1857 - graduated from West Point
1858 - was sent to Utah Expedition but did not make it before it was over
1858-1861 - teaching Signal Corps at West Point
1861-11/1862 - Chief of Ordinance i.e. supply master for Artillery

Not.That.Much.
I agree with your assessment of Alexander in many respects. However, his criticism seems to be the basis for most of the criticism directed at Lee for his decision the fight at Sharpsburg.

It is interesting to me that neither Jackson nor Longstreet seemed to disapprove of Lee's decision to fight. We know that Longstreet (especially) was not shy about voicing his disagreements with Lee's decisions in other places.

I have appreciated and enjoyed the discussion on this thread. Thank you everybody.
 
Agreed. As I've quoted before on a different thread (quoting Ethan Rafuse), if Sedgwick had been 15 minutes sooner or 15 minutes later it would have made a big difference.
Thinking about all this has reminded me of an essay I read that probably is the basis for everything I am saying. The article was A Failure of Command? A Reassessment of the Generalship of Edwin V. Sumner and the Federal II Corps at the Battle of Antietam by Marion V. Armstrong in Leadership and Command in the Civil War, edited by Steven E. Woodworth, 1996. That is a nice book for anyone interested in the topic.

That was far enough back that my copy was by Savas-Woodbury in 1996 (currently either Savas-Beattie or Savas Publishing, I think). Unfortunately, I loaned my copy to someone and it never came back. Oh, well. I'll be on a David Woodbury tour of Antietam this week, so maybe I can ask the guide, Tom Clemens, questions as we go.
 
Thinking about all this has reminded me of an essay I read that probably is the basis for everything I am saying. The article was A Failure of Command? A Reassessment of the Generalship of Edwin V. Sumner and the Federal II Corps at the Battle of Antietam by Marion V. Armstrong in Leadership and Command in the Civil War, edited by Steven E. Woodworth, 1996. That is a nice book for anyone interested in the topic.

That was far enough back that my copy was by Savas-Woodbury in 1996 (currently either Savas-Beattie or Savas Publishing, I think). Unfortunately, I loaned my copy to someone and it never came back. Oh, well. I'll be on a David Woodbury tour of Antietam this week, so maybe I can ask the guide, Tom Clemens, questions as we go.
Please do if you get a chance. I'd love to hear his take on it.

I've spent a bit of time trying to umderstand this part of the battle. Armstrong's writing (especially Unfurl Those Colors) is the basis my thinking as well.
 
Maybe (probably) Sumner should have had skirmishers out in front, but would that have made a huge difference in the outcome given the way Sedgwick's three brigades were deployed?
Sumner might have changed the formation of Sedgwick’s brigades if he knew that there were confederates in the Woods. From my understanding, the only real problem with the formation was that the brigades were too close together; they couldn’t maneuver, and all three brigades were vulnerable to enemy fire, but only the lead brigade could safely return fire. At one point the 59th New York of Dana’s brigade fired into the backs of the 15th Massachusetts of Gorman’s brigade.
 
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But not what his commander wanted him to do.
I’m still unclear on what Sumner wanted French to do. Was French’s division supposed to stay behind Sedgwick’s division and follow it into the West Woods, or was it supposed to move to the left and extend the Union line? French clearly thinks that he’s supposed to extend the line left. He doesn’t just wander off.
 
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I’m still unclear on what Sumner wanted French to do. Was French’s division supposed to stay behind Sedgwick’s division and follow it into the West Woods, or was it supposed to move to the left and extend the Union line? French clearly thinks that he’s supposed to extend the line left. He doesn’t just wander off.
I believe Sumner ordered French to go in on the left. Sumner's son delivered in order to that effect to French. I'm not sure that Sumner intended French to go as far left as he did. My question is whether or not Sumner knew Greene's division was located where it was at the time he planned his advance.
 
I’m still unclear on what Sumner wanted French to do. Was French’s division supposed to stay behind Sedgwick’s division and follow it into the West Woods, or was it supposed to move to the left and extend the Union line? French clearly thinks that he’s supposed to extend the line left. He doesn’t just wander off.

Things were constantly changing, sometimes minute by minute.

Sumner arrives at the front and discovers that things aren't as he expected when he left for the front. He runs into Hooker (wounded and in great pain) being carried from the field. Sumner asks Hooker what the situation is and Hooker tells him he thinks he has just won a great battle (Hooker would later testify he was in-and-out with the pain and really could not recall much of this.)

At this point, an aide arrives carrying orders from McClellan for Sumner and Hooker. Sumner reads both and it is clear that McClellan's view of the battle does not equate with the situation Sumner sees before him. He hasn't really been able to see the West Woods up until he passes through the East Woods. He does a quick personal recon, sees some Yankee troops near the northern end of the West Woods. At some point he does find out there are troops where Greene is, but I don't recall if he was ever in communication with Greene. Hooker has put Meade, his junior division commander, in charge before leaving. I think Sumner does get in communication with Meade briefly here as he tries to find out what the situation is, but I don't know what Meade would have known in detail about the mess going on where Sumner was.

Sumner's report has little detail:
SIR: I have the honor to report that, on the evening of the 16th ultimo, I received an order at Keedysville to send the Twelfth Corps (Banks') to support General Hooker, and to hold my own, the Second Corps, in readiness to march for the same purpose an hour before daylight. Banks' corps, under General Mansfield, marched at 11.30 p.m., and my own corps was ready to move at the time ordered, but did not receive from headquarters the order to march till 7.20 a.m. on the 17th. I moved Sedgwick's division immediately in three columns on the receipt of the order, followed by French's division in the same order. Richardson was ordered to move in the same direction by the commanding general about an hour later. On arriving at the place where Hooker had been engaged, I found him wounded, and his corps, after a severe contest, had been repulsed. Banks' corps, under the immediate command of General Mansfield, had gone into battle on Hooker's left, and was engaged when I came upon the field. General Mansfield, a worthy and gallant veteran, was unfortunately mortally wounded while leading his corps into action. My First Division (Sedgwick's) went into battle in three lines. After his first line had opened fire for some time, the enemy made a most determined rush to turn our left, and so far succeeded as to break through the line between Banks' corps and my own until they began to appear in our rear. In order to repel this attack from the rear, I immediately faced Sedgwick's third line about, but the fire at that moment became so severe from the left flank that this line moved off in a body to the right, in spite of all the efforts that could be made to stop it. The first and second lines after some time followed this movement, but the whole division was promptly rallied, took a strong position, and maintained it to the close of the battle. Richardson's and French's divisions maintained a furious and successful fight from the time they entered the battle till the end of it, highly to the honor of the officers and soldiers.​

Somewhere in the battle (no timestamp) McClellan received this:
To General MCCLELLAN:​
Re-enforcements are badly wanted. Our troops are giving way. I am hunting for French's and Slocum's divisions. If you know where they are, send them immediately.​
General SUMNER.​
French's report doesn't mention Greene at all:
COLONEL: My division, composed of Brig. Gen. Max Weber's and Kimball's brigades, and three regiments of new levies under the command of Col. Dwight Morris (Fourteenth Connecticut), having been in readiness since daybreak on the 17th instant, was put in motion by orders of the general commanding the corps at about 7.30 o'clock a.m. The Antietam Creek was forded by the division, marching in three columns of brigades, Max Weber on the left, the new regiments in the center, and Kimball's brigade on the right. When my left flank had cleared the ford a mile, the division faced to the left, forming three lines of battle adjacent to and contiguous with Sedgwick's, and immediately moved to the front.​

The enemy, who was in position in advance, opened his batteries, under which fire my lines steadily moved until the first line, encountering the enemy's skirmishers, charged them briskly, and, entering a group of houses on Roulette's farm, drove back the force, which had taken a strong position for defense. Whilst Max Weber was clearing his front and driving before him the enemy's first line, a sudden and terrible fire was opened upon his right by the troops, which had succeeded in breaking the center division of the line of battle. At the same time a heavy column endeavored to turn my left and rear.​

At this moment Captain Sumner communicated to me, from the general commanding the corps, that his right divisions were being severely handled, and directed me to press the enemy with all my force. Appreciating the necessity of the order, without waiting for the new regiments to recover from the disorder incident to their long march in line through woods, corn-fields, and over fences, I left them in reserve, and ordered Kimball to charge to the front. With an unsurpassed ardor this gallant brigade, sweeping over all obstacles, soon crowned the crests of the hills on our left and right, flaunting the regimental banners in defiance to those of the rebels who, flushed with a supposed victory, dared to face us.​

If Greene is in between them, you can't see it in those reports. French says his line was contiguous with Sedgwick, but that is pretty hard to picture unless it is before Sedgwick advanced on the West Woods.

Greene's report doesn't mention Sumner, Sedgwick or French at all:
The division was carried into action about 6.30 a.m., under the orders of Brigadier-General Mansfield. As we were going into action the Third Brigade was detached to the right, leaving under my command the First and Second Brigades, with an aggregate of 1,727. The division encountering the enemy in the first woods in our front drove them before it, and, entering the open ground partly covered with corn, moved to the left and took position on the right of the post and rail fence inclosing the field on the right of the burned house (Poffenberger's). There was a battery of brass guns at our left, which we protected. This battery getting out of ammunition for long range was replaced by another.​
While in this position the enemy formed in strong force in the woods to the right of the white brick church and advanced on our line. The line was advanced to the axle-trees of the guns, and delivered their fire when the enemy were within 70 yards. They immediately fell back, having suffered immense loss. The division advanced, driving the enemy from the woods near the church and occupying the woods. The Purnell Legion joined us during the action. The Twenty-seventh Indiana was sent to our support, and, after doing good service, retired in consequence of their ammunition being exhausted. The Thirteenth New Jersey then joined the division, and assisted in holding the woods. The position of the division in the advanced woods was very critical. We were in advance of our line on the right and left of us. Sumner's corps, which had advanced on our left, had retired, as had also the troops on our right. Guns were sent for, and a section of Knap's battery arrived, and were ordered to take position on our left. The ground on our left and front was broken and wooded, and concealed the movements of the enemy. I placed the division in line, with the right thrown back, and sent forward skirmishers and sought re-enforcements from General Williams. None were at the time available, and the enemy advancing in large force, threatening to envelop the small command, they were forced to retire. They rallied in the second line of woods. They held the woods by the church nearly two hours, in advance of any other troops in their vicinity. They were in action from 6.30 a.m. to 1.30 p.m.​

So if you just go by the official reports, these generals didn't know much at all about what was going on with each other.

LATER: On re-reading, I see that Greene thought Sumner had advanced and then retreated on his left. He apparently doesn't know that the troops that advanced and then retreated on his right were also Sumner's Corps.
 
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I believe Sumner ordered French to go in on the left. Sumner's son delivered in order to that effect to French. I'm not sure that Sumner intended French to go as far left as he did. My question is whether or not Sumner knew Greene's division was located where it was at the time he planned his advance.

What follows is from Marion Armstrong's Unfurl Those Colors: McClellan, Sumner, and the Second Army Corps in the Antietam Campaign.

This is when Sumner has reached the East Woods and is trying to figure out what the situation is. The earlier fighting has left casualties throughout this area and some firing is still going on. Hooker is wounded and Sumner has seen him being carried off. He has just sent his staff officers off to find out what they can. All he can see of the West Woods is the tops of the trees because of the ridge in between the East Woods and the West Woods.

1556750786683.png

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So, that's about what Sumner knows when he orders Sedgwick forward out of the East Woods, over the ridge, and into the West Woods.
 
From Marion Armstrong's Unfurl Those Colors: McClellan, Sumner, and the Second Army Corps in the Antietam Campaign.

This is the situation just as Sumner and Sedgwick gets to the West Woods:

1556752450940.png


I'm looking at a limited preview, so the pages about French's actual orders aren't available to me.
 
From Marion Armstrong's Unfurl Those Colors: McClellan, Sumner, and the Second Army Corps in the Antietam Campaign.

This is the situation just as Sumner and Sedgwick gets to the West Woods:

View attachment 305400

I'm looking at a limited preview, so the pages about French's actual orders aren't available to me.
When I get a chance I'll look it up. I have the book as well as Opposing the Second Corps at Antietam. I've read both but have actually thought about reading again to get a better grip on the West Woods fight specifically.
 
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