Lee had now accomplished the first of his two purposes. He had raised McClellan's siege of Richmond. He had not succeeded in capturing or destroying McClellan's army as he had hoped to do, but he had completely baffled its endeavor. He had driven it out of its strongly fortified positions. He had kept it in an enforced and continuous retreat for a whole week. He had compelled it to fight losing battles by day, and to spend the nights in painful and exhausting efforts to escape, which McClellan himself, as his grieved and angry official reports clearly showed, regarded as efforts of extremely doubtful outcome. McClellan's campaign against Richmond had disastrously failed. He had saved his army indeed without a repetition of the Manassas panic, but he had been baffled in all his purposes and driven for seven days and nights like a hunted stag seeking safety in flight. All his combinations had come to naught, all his elaborately constructed earthworks had failed him even as means of holding his position as an assailant. All his siege guns had proved of no avail. But he had organized a great army so well disciplined that it could fight with determination, lose with a calm mind, and retreat before a pursuing enemy without losing cohesion or falling into panic. That service of his was emphasized during all the brilliant future history of the Army of the Potomac. It made itself manifest at Antietam, at Fredericksburg, at Chancellorsville, at Gettysburg, and later at the Wilderness, Spottsylvania, Cold Harbor and Petersburg. But with all his splendid ability as an engineer, and his still more conspicuous gifts as an organizer of raw material into an effective force, McClellan was manifestly unfit to command an expedition in which he must try his wits against the genius of Robert E. Lee and Stonewall Jackson. A historian most friendly to him, Dr. Rossiter Johnson, has written: "He was an accomplished engineer and a gigantic adjutant, but hardly the general to be sent against an army that could move and a commander that could think." Lee had driven a splendid army, nearly double his own in numbers, to a position where it lay cowering on the river-bank, under protection of the gunboats and no longer depending upon its own prowess even for self-defense.