The battle of Williamsburg was strategically of no consequence except as a part of a campaign of delay. It would be an idle waste of space, a needless taxing of the reader's attention, to recount its strategy in detail. It is sufficient to say that after delaying McClellan's advance for two days and inflicting a heavy loss upon him, the Confederates withdrew in good order to the main defenses of Richmond.
McClellan now sent Franklin's division on transports to the White House at the head of the York river, to establish there a secure base of supplies. The whole army followed and by the sixteenth of May it was concentrated there.
This was then the situation. McClellan lay at the White House within twenty-four miles of Richmond. He had more nearly three than two men to his adversary's one under his immediate command and he had an army nearly equal to his enemy's, within two or three days' march ready to reinforce him, or better still, to assail his adversary in flank.
A general of such enterprise as General Sheridan, or General Sherman, or General Grant, or General Thomas, placed in such circumstances, would unquestionably have pressed forward to the assault.
But McClellan's timid imagination swelled Johnston's force of 50,000 or less to 120,000 or more and he hesitated. Instead of pushing forward by the shortest roads to Richmond he scientifically "developed" his force along the Chickahominy river to the north of Richmond, and, after fortifying, made a requisition for reinforcements.
In the meanwhile "Stonewall" Jackson had achieved some brilliant successes in the Shenandoah Valley which so far seemed to threaten Washington with assault, that McDowell's force of 40,000 men was recalled from its march to reinforce McClellan and sent to ward off the danger of an advance upon the Federal capital by that peculiarly energetic and enterprising commander.
But even without McDowell's expected reinforcement, McClellan had greatly more than twice his adversary's force. It is impossible to doubt that if he had been moved by anything like Grant's habitual and determined impulse to "press things" he would promptly have hurled his overwhelming force against his adversary's defensive lines.
McClellan, however, was not Grant nor such as he. He had a superior skill in the theoretical science of war but an immeasurably inferior capacity for war's practical work.
North of Richmond and from five to seven miles distant the Chickahominy river runs in a course almost due east from its source. McClellan placed his main force north of that erratic and uncertain stream and there awaited the reinforcements for which he was clamorously calling. But he threw his left wing across the river to the Richmond side of it. Unless he were prepared to advance at once with all his force and assail the Confederate works this was an exceedingly dangerous thing to do, for the Chickahominy is a phenomenally uncertain and erratic river. In dry weather it is scarcely more than a brook, but in periods of rain—and spring in Virginia is a rainy season—it swells suddenly and quickly to almost impassable proportions, while the swamps that form its banks become morasses in which it is difficult to find even a foothold, and impossible to discover a fit camping place for troops. When McClellan established his left wing south of the river the stream presented no obstacle to its prompt reinforcement from the other side in case of need. But presently the windows of heaven were opened and the fountains of the great deep were broken up. The floods came, and this isolated left wing was cut off and left mainly to its own devices for self-maintenance.
The Confederate General Johnston was quick to see and seize this opportunity. On the morning of the thirty-first of May, he assailed the detached left wing and there resulted the two-days' battle called Fair Oaks at the North, and Seven Pines at the South.