the invading army. "An advance east of
the Blue Ridge," he said, "would at once menace the enemy's line of
communications, and compel him to keep his forces together; and if
Lee, disregarding this menace, were to cut in between the Army of the
Potomac and Washington, McClellan would have nothing to do but to
attack him in rear." He suggested, moreover, that by hard marching it
might be possible for McClellan to reach Richmond first.

The Confederate line of communications, so the President believed,
ran from Richmond to Culpeper Court House, and McClellan's advanced
guards, on November 7, were within twenty miles of that point. Lee,
however, had altogether failed to respond to Mr. Lincoln's
strategical pronouncements. Instead of concentrating his forces he
had dispersed them; and instead of fearing for his own
communications, he had placed Jackson in a position to interfere very
seriously with those of his enemy.

Mr. Lincoln's letter to McClellan shows that the lessons of the war
had not been altogether lost upon him. Generals Banks and Pope, with
some stimulus from Stonewall Jackson, had taught him what an
important part is played by lines of supply. He had mastered the
strategical truism that an enemy's communications are his weakest
point. But there were other considerations which had not come home to
him. He had overlooked the possibility that Lee might threaten
McClellan's communications before McClellan could threaten his; and
he had yet to learn that an army operating in its own country, if
proper forethought be exercised, can establish an alternative line of
supply, and provide itself with a double base, thus gaining a freedom
of action of which an invader, bound, unless he has command of the
sea, to a single line, is generally deprived.

The President appears to have thought that, if Lee were cut off from
Richmond, the Army of Northern Virginia would be reduced to
starvation, and become absolutely powerless. It never entered his
head that the astute commander of that army had already, in
anticipation of the very movement which McClellan was now making,
established a second base at Staunton, and that his line of supply,
in case of necessity, would not run over the open country between
Richmond and Gordonsville, but from Staunton to Culpeper, behind the
ramparts of the Blue Ridge.

Lee, in fact, accepted with equanimity the possibility of the
Federals intervening between himself and Richmond. He had alread