Lee, with D. H. Hill, Longstreet, and Stuart, was already falling back from the South Mountain to Sharpsburg, a little village on the right bank of the Antietam Creek; and late in the afternoon Jackson, Walker, and McLaws were ordered to rejoin without delay.[[23]] September 14 had been an anxious day for the Confederate Commander-in-Chief. During the morning D. H. Hill, with no more than 5,000 men in his command, had seen the greater part of McClellan’s army deploy for action in the wide valley below and to the eastward of Turner’s Gap. Stuart held the woods below Crampton’s Gap, six miles south, with Robertson’s brigade, now commanded by the gallant Munford; and on the heights above McLaws had posted three brigades, for against this important pass, the shortest route by which the Federals could interpose between Lee and Jackson, McClellan’s left wing, consisting of 20,000 men under General Franklin, was steadily advancing.
The positions at both Turner’s and Crampton’s Gaps were very strong. The passes, at their highest points, are at least 600 feet above the valley, and the slopes steep, rugged, and thickly wooded. The enemy’s artillery had little chance. Stone walls, running parallel to the crest, gave much protection to the Southern infantry, and loose boulders and rocky scarps increased the difficulties of the ascent. But the numbers available for defence were very small; and had McClellan marched during the night he would probably have been master of the passes before midday. As it was, Crampton’s Gap was not attacked by Franklin until noon; and although at the same hour the advanced guard of the Federal right wing had gained much ground, it was not till four in the evening that a general attack was made on Turner’s Gap. By this time Longstreet, after a march of thirteen miles, had reached the battle-field;[[24]] and despite the determination with which the attack was pressed, Turner’s Gap was still held when darkness fell.
The defence of Crampton’s Gap had been less successful. Franklin had forced the pass before five o’clock, and driving McLaws’ three brigades before him, had firmly established himself astride the summit. The Confederate losses were larger than those which they had inflicted. McClellan reports 1,791 casualties on the right, Franklin 533 on the left. McLaws’ and Munford’s loss was over 800, of whom 400 were captured. The number of killed and wounded in Hill’s and Longstreet’s commands is unknown; it probably reached a total of 1,500, and 1,100 of their men were marched to Frederick as prisoners. Thus the day’s fighting had cost the South 3,400 men. Moreover, Longstreet’s ammunition column, together with an escort of 600 men, had been cut up by the cavalry which had escaped from Harper’s Ferry, and which had struck the Hagerstown road as it marched northward into Pennsylvania. Yet, on the whole, Lee had no reason to be chagrined with the result of his operations. McClellan had acted with unexpected vigour. But neither in strategy nor in tactics had he displayed improvement on his Peninsular methods. He should have thrown the bulk of his army against Crampton’s Gap, thus intervening between Lee and Jackson; but instead of doing so he had directed 70,000 men against Turner’s Gap. Nor had the attack on Hill and Longstreet been characterised by resolution. The advanced guard was left unsupported until 2 p.m., and not more than 30,000 men were employed throughout the day. Against this number 8,000 Confederates had held the pass. Cobb, one of McLaws’ brigadiers, who commanded the defence at Crampton’s Gap, though driven down the mountain, had offered a stout resistance to superior forces; and twenty-four hours had been gained for Jackson. On the other hand, in face of superior numbers, the position at Turner’s Gap had become untenable; and during the night Hill and Longstreet marched to Sharpsburg.
Sept. 15 This enforced retreat was not without effect on the moral of either army. McClellan was as exultant as he was credulous. “I have just learned,” he reported to Halleck at 8 a.m. on the 15th, “from General Hooker, in advance, that the enemy is making for Shepherdstown in a perfect panic; and that General Lee last night stated publicly that he must admit they had been shockingly whipped. I am hurrying forward to endeavour to press their retreat to the utmost.” Then, two hours later: “Information this moment received completely confirms the rout and demoralisation of the rebel army. It is stated that Lee gives his losses as 15,000. We are following as rapidly as the men can move.”[[25]] Nor can it be doubted that McClellan’s whole army, unaccustomed to see their antagonists give ground before them, shared the general’s mood.[[26]] Amongst the Confederates, on the other hand, there was some depression. It could not be disguised that a portion of the troops had shown symptoms of demoralisation. The retreat to the Antietam, although effectively screened by Fitzhugh Lee’s brigade of cavalry, was not effected in the best of order. Many of the regiments had been broken by the hard fighting on the mountain; men had become lost in the forest, or had sought safety to the rear; and the number of stragglers was very large. It was not, then, with its usual confidence that the army moved into position on the ridge above the Antietam Creek. General Longstreet, indeed, was of opinion that the army should have recrossed the Potomac at once. “The moral effect of our move into Maryland had been lost by our discomfiture at South Mountain, and it was evident we could not hope to concentrate in time to do more than make a respectable retreat, whereas by retiring before the battle [of Sharpsburg] we could have claimed a very successful campaign.”[[27]] So spake the voice of prudence. Lee, however, so soon as he was informed of the fall of Harper’s Ferry, had ordered Jackson to join him, resolving to hold his ground, and to bring McClellan to a decisive battle on the north bank of the Potomac.
Although 45,000 men—for Lee at most could count on no more than this number, so great had been the straggling—were about to receive the attack of over 90,000, Jackson, when he reached Sharpsburg on the morning of the 16th, heartily approved the Commander-in-Chief’s decision, and it is worth while to consider the reasons which led them to disagree with Longstreet.
1. Under ordinary conditions, to expect an army of 45,000 to wrest decisive victory from one of 90,000 well-armed enemies would be to demand an impossibility. The defence, when two armies are equally matched, is physically stronger than the attack, although we have Napoleon’s word for it that the defence has the harder task. But that the inherent strength of the defence is so great as to enable the smaller force to annihilate its enemy is contrary to all the teaching of history. By making good use of favourable ground, or by constructing substantial works, the smaller force may indeed stave off defeat and gain time. But it can hope for nothing more. The records of warfare contain no instance, when two armies were of much the same quality, of the smaller army bringing the campaign to a decisive issue by defensive tactics. Wellington and Lee both fought many defensive battles with inferior forces. But neither of them, under such conditions, ever achieved the destruction of their enemy. They fought such battles to gain time, and their hopes soared no higher. At Talavera, Busaco, Fuentes d’Onor, where the French were superior to the allies, Wellington repulsed the attack, but he did not prevent the defeated armies taking the field again in a few days. At the Wilderness, Spotsylvania, the North Anna, and Cold Harbour, the great battles of 1864, Lee maintained his ground, but he did not prevent Grant moving round his flank in the direction of Richmond. At the Second Manassas, Jackson stood fast for the greater part of two days, but he would never have driven Pope across Bull Run without the aid of Longstreet. Porter at Gaines’ Mill held 55,000 men with 35,000 for more than seven hours, but even if he had maintained his position, the Confederate army would not have become a mob of fugitives. No; except on peculiarly favourable ground, or when defending an intrenched camp, an army matched with one of equal efficiency and numerically superior, can never hope for decisive success. So circumstanced, a wise general will rather retreat than fight, and thus save his men for a more favourable opportunity.[[28]]
But Lee and Jackson had not to deal with ordinary conditions. Whatever may have been the case in the Peninsula and in the Valley, there can be no question but that the armies in Maryland were by no means equal in quality. The Federals were far more accustomed to retreat than advance. For several months, whether they were engaged on the Shenandoah, on the Chickahominy, on the Rappahannock, or on Bull Run, they had been invariably outmanœuvered. Their losses had been exceedingly severe, not only in battle, but from sickness and straggling. Many of their bravest officers and men had fallen. With the exception of the Second and Sixth Army Corps, commanded by Sumner and by Franklin, by far the greater part of the troops had been involved in Pope’s defeat, and they had not that trust in their leaders which promises a strong offensive. While at Washington the army had been reinforced by twenty-four regiments of infantry, but the majority of these troops had been but lately raised; they knew little of drill; they were commanded by officers as ignorant as themselves, and they had never fired a musket. Nor were the generals equal in capacity to those opposing them. “If a student of history,” says a Northern officer, “familiar with the characters who figured in the War of Secession, but happening to be ignorant of the battle of Antietam, should be told the names of the men who held high commands there, he would say that with anything like equality of forces the Confederates must have won, for their leaders were men who made great names in the war, while the Federal leaders were, with few exceptions, men who never became conspicuous, or became conspicuous only through failure.”[[29]] And the difference in military capacity extended to the rank and file. When the two armies met on the Antietam, events had been such as to confer a marked superiority on the Southerners. They were the children of victory, and every man in the army had participated in the successes of Lee and Jackson. They had much experience of battle. They were supremely confident in their own prowess, for the fall of Harper’s Ferry had made more than amends for the retreat from South Mountain, and they were supremely confident in their leaders. No new regiments weakened the stability of their array. Every brigade and every regiment could be depended on. The artillery, which had been but lately reorganised in battalions, had, under the fostering care of General Pendleton, become peculiarly efficient, although the materiel was still indifferent; and against Stuart’s horsemen the Federal cavalry was practically useless.
In every military attribute, then, the Army of Northern Virginia was so superior to the Army of the Potomac that Lee and Jackson believed that they might fight a defensive battle, outnumbered as they were, with the hope of annihilating their enemy. They were not especially favoured by the ground, and time and means for intrenching were both wanting; but they were assured that not only were their veterans capable of holding the position, but, if favoured by fortune, of delivering a counterstroke which should shiver the Army of the Potomac into a thousand fragments.
2. By retreating across the Potomac, in accordance with General Longstreet’s suggestion, Lee would certainly have avoided all chances of disaster. But, at the same time, he would have abandoned a good hope of ending the war. The enemy would have been fully justified in assuming that the retrograde movement had been made under the compulsion of his advance, and the balance of moral have been sensibly affected in favour of the Federals. If the Potomac had once been placed between the opposing forces, McClellan would have had it in his power to postpone an encounter until his army was strongly reinforced, his raw regiments trained, and his troops rested. The passage of the river, it is true, had been successfully forced by the Confederates on September 5. But it by no means followed that it could be forced for the second time in face of a concentrated enemy, who would have had time to recover his moral and supply his losses. McClellan, so long as the Confederates remained in Maryland, had evidently made up his mind to attack. But if Maryland was evacuated he would probably content himself with holding the line of the Potomac; and, in view of the relative strength of the two armies, it would be an extraordinary stroke of fortune which should lay him open to assault. Lee and Jackson were firmly convinced that it was the wiser policy to give the enemy no time to reorganise and recruit, but to coerce him to battle before he had recovered from the defeat which he had sustained on the heights above Bull Run. To recross the Potomac would be to slight the favours of fortune, to abandon the initiative, and to submit, in face of the vast numbers of fresh troops which the North was already raising, to a defensive warfare, a warfare which might protract the struggle, but which must end in the exhaustion of the Confederacy. McClellan’s own words are the strongest justification of the views held by the Southern leaders:—
“The Army of the Potomac was thoroughly exhausted and depleted by the desperate fighting and severe marching in the unhealthy regions of the Chickahominy and afterwards, during the second Bull Run campaign; its trains, administrative services and supplies were disorganised or lacking in consequence of the rapidity and manner of its removal from the Peninsula, as well as from the nature of its operations during the second Bull Run campaign.