did take place, General Lee
was in a position to interpose his army, and inflict a new defeat on the enemy, as was verified by subsequent events.
The following extracts from McClellan
's report will give some idea of the results obtained.
Speaking, as of the morning of the 18th, he says:
At that moment-Virginia lost, Washington menaced, Maryland invaded — the national cause could afford no risks of defeat.
Our battle lost, and almost all would have been lost.
And he subsequently says:
The movement from Washington into Maryland, which culminated in the battles of South Mountain and Antietam, was not a part of an offensive campaign, with the object of the invasion of the enemy's territory, and an attack on his capital, but was defensive in its purposes, although offensive in its character, and would be technically called a “ defensive-offensive” campaign.
It was undertaken at a time: when our army had experienced severe defeats, and its object was to preserve the national capital and Baltimore, to protect Pennsylvania, and to drive the enemy out of Maryland.
These purposes were fully and finally accomplished by the battle of Antietam, which brought the Army of the Potomac into what might be termed an accidental position on the upper Potomac.1
It was a great deal gained to force the enemy into a “defensive-offensive” campaign in his own territory and place the Army of the Potomac in that accidental position, though we did fail in arousing Maryland
, or getting any reinforcements from that State.