This order of March 11 included also the already mentioned consolidation of the western departments under Halleck; and out of the region lying between Halleck's command and McClellan's command it created the Mountain Department, the command of which he gave to General Frémont, whose reinstatement had been loudly clamored for by many prominent and enthusiastic followers.
As the preparations for a movement by water had been in progress since February 27, there was little delay in starting the Army of the Potomac on its new campaign. The troops began their embarkation on March 17, and by April 5 over one hundred thousand men, with all their material of war, had been transported to Fortress Monroe, where General McClellan himself arrived on the second of the month, and issued orders to begin his march on the fourth.
Unfortunately, right at the outset of this new campaign, General McClellan's incapacity and want of candor once more became sharply evident. In the plan formulated by the four corps commanders, and approved by himself, as well as emphatically repeated by the President's instructions, was the essential requirement that Washington should be left entirely secure. Learning that the general had neglected this positive injunction, the President ordered McDowell's corps to remain for the protection of the capital; and when the general complained of this, Mr. Lincoln wrote him on April 9:
"After you left I ascertained that less than twenty thousand unorganized men, without a single field-battery, were all you designed to be left for the defense of Washington and Manassas Junction; and part of this, even, was to go to General Hooker's old position. General Banks's corps, once designed for Manassas Junction, was divided and tied up on the line of Winchester and Strasburg, and could not leave it without again exposing the upper Potomac and the Baltimore and Ohio railroad. This presented (or would present when McDowell and Sumner should be gone) a great temptation to the enemy to turn back from the Rappahannock and sack Washington. My explicit order that Washington should, by the judgment of all the commanders of corps, be left entirely secure, had been neglected. It was precisely this that drove me to detain McDowell.
"I do not forget that I was satisfied with your arrangement to leave Banks at Manassas Junction; but when that arrangement was broken up and nothing was substituted for it, of course I was not satisfied. I was constrained to substitute something for it myself."
"And now allow me to ask, do you really think I should permit the line from Richmond via Manassas Junction to this city to be entirely open, except what resistance could be presented by less than twenty thousand unorganized troops? This is a question which the country will not allow me to evade...."
"By delay, the enemy will relatively gain upon you—that is, he will gain faster by fortifications and reinforcements than you can by reinforcements alone. And once more let me tell you it is indispensable to you that you strike a blow. I am powerless to help this. You will do me the justice to remember I always insisted that going down the bay in search of a field, instead of fighting at or near Manassas, was only shifting and not surmounting a difficulty; that we would find the same enemy and the same or equal intrenchments at either place. The country will not fail to note—is noting now—that the present hesitation to move upon an intrenched enemy is but the story of Manassas repeated."
General McClellan's expectations in coming to the Peninsula, first, that he would find few or no rebel intrenchments, and, second, that he would be able to make rapid movements, at once signally failed. On the afternoon of the second day's march he came to the first line of the enemy's defenses, heavy fortifications at Yorktown on the York River, and a strong line of intrenchments and dams flooding the Warwick River, extending to an impassable inlet from James River. But the situation was not yet desperate. Magruder, the Confederate commander, had only eleven thousand men to defend Yorktown and the thirteen-mile line of the Warwick. McClellan, on the contrary, had fifty thousand at hand, and as many more within call, with which to break the Confederate line and continue his proposed "rapid movements." But now, without any adequate reconnaissance or other vigorous effort, he at once gave up his thoughts of rapid movement, one of the main advantages he had always claimed for the water route, and adopted the slow expedient of a siege of Yorktown. Not alone was his original plan of campaign demonstrated to be faulty, but by this change in the method of its execution it became fatal.
It would be weary and exasperating to recount in detail the remaining principal episodes of McClellan's operations to gain possession of the Confederate capital. The whole campaign is a record of hesitation, delay, and mistakes in the chief command, brilliantly relieved by the heroic fighting and endurance of the troops and subordinate officers, gathering honor out of defeat, and shedding the luster of renown over a result of barren failure. McClellan wasted a month raising siege-works to bombard Yorktown, when he might have turned the place by two or three days' operations with his superior numbers of four to one. By his failure to give instructions after Yorktown was evacuated, he allowed a single division of his advance-guard to be beaten back at Williamsburg, when thirty thousand of their comrades were within reach, but without orders. He wrote to the President that he would have to fight double numbers intrenched, when his own army was actually twice as strong as that of his antagonist. Placing his army astride the Chickahominy, he afforded that antagonist, General Johnston, the opportunity, at a sudden rise of the river, to fall on one portion of his divided forces at Fair Oaks with overwhelming numbers. Finally, when he was within four miles of Richmond and was attacked by General Lee, he began a retreat to the James River, and after his corps commanders held the attacking enemy at bay by a successful battle on each of six successive days, he day after day gave up each field won or held by the valor and blood of his heroic soldiers. On July 1, the collected Union army made a stand at the battle of Malvern Hill, inflicting a defeat on the enemy which practically shattered the Confederate army, and in the course of a week caused it to retire within the fortifications of Richmond. During all this magnificent fighting, however, McClellan was oppressed by the apprehension of impending defeat; and even after the brilliant victory of Malvern Hill, continued his retreat to Harrison's Landing, where the Union gunboats on the James River assured him of safety and supplies.
It must be borne in mind that this Peninsula campaign, from the landing at Fortress Monroe to the battle at Malvern Hill, occupied three full months, and that during the first half of that period the government, yielding to McClellan's constant faultfinding and clamor for reinforcements, sent him forty thousand additional men; also that in the opinion of competent critics, both Union and Confederate, he had, after the battle of Fair Oaks, and twice during the seven days' battles, a brilliant opportunity to take advantage of Confederate mistakes, and by a vigorous offensive to capture Richmond. But constitutional indecision unfitted him to seize the fleeting chances of war. His hope of victory was always overawed by his fear of defeat. While he commanded during a large part of the campaign double, and always superior, numbers to the enemy, his imagination led him continually to double their strength in his reports. This delusion so wrought upon him that on the night of June 27 he sent the Secretary of War an almost despairing and insubordinate despatch, containing these inexcusable phrases: