That Jackson divined the full effect of his attack would be to assert too much. That he realised that the battle, though a tactical defeat, was strategically a victory is very evident. He knew something of Banks, he knew more of McClellan, and the bearing of the Valley on the defence of Washington had long been uppermost in his thoughts. He had learned from Napoleon to throw himself into the spirit of his enemy, and it is not improbable that when he stood before the fire near Newtown he had already foreseen, in some degree at least, the events that would follow the news of his attack at Kernstown.
The outcome of the battle was indeed far-reaching. “Though the battle had been won,” wrote Shields, “still I could not have believed that Jackson would have hazarded a decisive engagement, so far from the main body, without expecting reinforcements; so, to be prepared for such a contingency, I set to work during the night to bring together all the troops within my reach. I sent an express after Williams’ division, requesting the rear brigade, about twenty miles distant, to march all night and join me in the morning. I swept the posts in rear of almost all their guards, hurrying them forward by forced marches, to be with me at daylight.”[[23]]
General Banks, hearing of the engagement on his way to Washington, halted at Harper’s Ferry, and he also ordered Williams’ division to return at once to Winchester.
One brigade only,[[24]] which the order did not reach, continued the march to Manassas. This counter-movement met with McClellan’s approval. He now recognised that Jackson’s force, commanded as it was, was something more than a mere corps of observation, and that it was essential that it should be crushed. “Your course was right,” he telegraphed on receiving Banks’ report. “As soon as you are strong enough push Jackson hard and drive him well beyond Strasburg. . . . The very moment the thorough defeat of Jackson will permit it, resume the movement on Manassas, always leaving the whole of Shields’ command at or near Strasburg and Winchester until the Manassas Gap Railway is fully repaired. Communicate fully and act vigorously.”[[25]]
8,000 men (Williams’ division) were thus temporarily withdrawn from the force that was to cover Washington from the south. But this was only the first step. Jackson’s action had forcibly attracted the attention of the Federal Government to the Upper Potomac. The President was already contemplating the transfer of Blenker’s division from McClellan to Fremont; the news of Kernstown decided the question, and at the end of March these 9,000 men were ordered to West Virginia, halting at Strasburg, in case Banks should then need them, on their way.[[26]] But even this measure did not altogether allay Mr. Lincoln’s apprehensions. McClellan had assured him, on April 1, that 73,000 men would be left for the defence of the capital and its approaches. But in the original arrangement, with which the President had been satisfied, Williams was to have been brought to Manassas, and Shields alone left in the Shenandoah Valley. Under the new distribution the President found that the force at Manassas would be decreased by two brigades; and, at the same time, that while part of the troops McClellan had promised were not forthcoming, a large portion of those actually available were good for nothing. The officer left in command at Washington reported that “nearly all his force was imperfectly disciplined; that several of the regiments were in a very disorganised condition; that efficient artillery regiments had been removed from the forts, and that he had to relieve them with very new infantry regiments, entirely unacquainted with the duties of that arm.”[[27]] Lincoln submitted the question to six generals of the regular army, then present in Washington; and these officers replied that, in their opinion, “the requirement of the President that this city shall be left entirely secure has not been fully complied with.”[[28]]
On receiving this report, Lincoln ordered the First Army Corps, 37,000 strong, under General McDowell, to remain at Manassas in place of embarking for the Peninsula; and thus McClellan, on the eve of his advance on Richmond, found his original force of 150,000 reduced by 46,000 officers and men. Moreover, not content with detaching McDowell for a time, Lincoln, the next day, assigned that general to an independent command, covering the approaches to Washington; Banks, also, was withdrawn from McClellan’s control, and directed to defend the Valley. The original dissemination of the Federal forces was thus gravely accentuated, and the Confederates had now to deal with four distinct armies, McClellan’s, McDowell’s, Banks’, and Fremont’s, dependent for co-operation on the orders of two civilians, President Lincoln and his Secretary of War. And this was not all. McDowell had been assigned a most important part in McClellan’s plan of invasion. The road from Fortress Monroe was barred by the fortifications of Yorktown. These works could be turned, however, by sending a force up the York River. But the passage of the stream was debarred to the Federal transports by a strong fort at Gloucester Point, on the left bank, and the capture of this work was to be the task of the First Army Corps. No wonder that McClellan, believing that Johnston commanded 100,000 men, declared that in his deliberate judgment the success of the Federal cause was imperilled by the order which detached McDowell from his command. However inadequately the capital might be defended, it was worse than folly to interfere with the general’s plans when he was on the eve of executing them. The best way of defending Washington was for McClellan to march rapidly on Richmond, and seize his adversary by the throat. By depriving him of McDowell, Lincoln and his advisers made such a movement difficult, and the grand army of invasion found itself in a most embarrassing situation. Such was the effect of a blow struck at the right place and the right time, though struck by no more than 3,000 bayonets.
The battle of Kernstown was undoubtedly well fought. It is true that Jackson believed that he had no more than four regiments of infantry, a few batteries, and some cavalry before him. But it was a skilful manœuvre, which threw three brigades and three batteries, more than two-thirds of his whole strength, on his opponent’s flank. An ordinary general would probably have employed only a small portion of his force in the turning movement. Not so the student of Napoleon. “In the general’s haversack,” says one of Jackson’s staff, “were always three books: the Bible, Napoleon’s Maxims of War, and Webster’s Dictionary—for his spelling was uncertain—and these books he constantly consulted.” Whether the chronicles of the Jewish kings threw any light on the tactical problem involved at Kernstown may be left to the commentators; but there can be no question as to the Maxims. To hurl overwhelming numbers at the point where the enemy least expects attack is the whole burden of Napoleon’s teaching, and there can be no doubt but that the wooded ridge, unoccupied save by a few scouts, was the weakest point of the defence.
The manœuvre certainly surprised the Federals, and it very nearly beat them. Tyler’s brigade was unsupported for nearly an hour and a half. Had his battalions been less staunch, the tardy reinforcements would have been too late to save the day. Coming up as they did, not in a mass so strong as to bear all before it by its own inherent weight, but in successive battalions, at wide intervals of time, they would themselves have become involved in a desperate engagement under adverse circumstances. Nor is Kimball to be blamed that he did not throw greater weight on Jackson’s turning column at an earlier hour. Like Shields and Banks, he was unable to believe that Jackson was unsupported. He expected that the flank attack would be followed up by one in superior numbers from the front. He could hardly credit that an inferior force would deliberately move off to a flank, leaving its line of retreat to be guarded by a few squadrons, weakly supported by infantry; and the audacity of the assailant had the usual effect of deceiving the defender.
Kernstown, moreover, will rank as an example of what determined men can do against superior numbers. The Confederates on the ridge, throughout the greater part of the fight, hardly exceeded 2,000 muskets. They were assailed by 3,000, and proved a match for them. The 3,000 were then reinforced by at least 3,000 more, whilst Jackson could bring up only 600 muskets to support an already broken line. Nevertheless, these 6,000 Northerners were so roughly handled that there was practically no pursuit. When the Confederates fell back every one of the Federal regiments had been engaged, and there were no fresh troops wherewith to follow them. Jackson was perfectly justified in reporting that “Night and an indisposition of the enemy to press further terminated the battle.”[[29]]
But the action was attended by features more remarkable than the stubborn resistance of the Virginia regiments. It is seldom that a battle so insignificant as Kernstown has been followed by such extraordinary results. Fortune indeed favoured the Confederates. At the time of the battle a large portion of McClellan’s army was at sea, and the attack was delivered at the very moment when it was most dreaded by the Northern Government. Nor was it to the disadvantage of the Southerners that the real head of the Federal army was the President, and that his strategical conceptions were necessarily subservient to the attitude of the Northern people. These were circumstances purely fortuitous, and it might seem, therefore, that Jackson merely blundered into success. But he must be given full credit for recognizing that a blow at Banks might be fraught with most important consequences. It was with other ideas than defeating a rear-guard or detaining Banks that he seized the Kernstown ridge. He was not yet aware of McClellan’s plan of invasion by sea; but he knew well that any movement that would threaten Washington must prove embarrassing to the Federal Government; that they could not afford to leave the Upper Potomac ill secured; and that the knowledge that an active and enterprising enemy, who had shown himself determined to take instant advantage of every opportunity, was within the Valley, would probably cause them to withdraw troops from McClellan in order to guard the river. A fortnight after the battle, asking for reinforcements, he wrote, “If Banks is defeated it may greatly retard McClellan’s movements.”[[30]]