William Swinton, Campaigns of the Army of the Potomac

It need hardly be said that this protracted delay at the moment the army was manoeuvring to fight a great battle, however necessary General Burnside may have deemed it,¹ was likely seriously to jeopardize the opportunity presented by the scattered condition of Lee's forces when the army reached Warrenton. At that time the Confederate right, under Longstreet, was near Culpepper, and the left, under Jackson, in the Shenandoah Valley—the two wings being separated by two marches; and it had been General McClellan's intent, by a rapid advance on Gordonsville, to interpose between Lee's divided forces. But this was not a matter that touched Burnside's plan; for he had already resolved to abandon offensive action on that line, and was determined to make a change of base to Fredericksburg on the Rappahannock.

It would be difficult to explain this determination on any sound military principle; for while the destruction of the hostile army was, in the very nature of things, the prime aim and object of the campaign, General Burnside turned his back on that army, and set out upon a seemingly aimless adventure to the Rappahannock, whither, in fact, Lee had to run in search of him. If it be said that Richmond was General Burnside's objective point, and that, regarding this rather than the hostile force, he chose the Fredericksburg line as one presenting fewer difficulties than that on which the army was moving (the line of the Orange and Alexandria Railroad), the reply is, that an advance against Richmond was, at this season, impracticable by any line; but a single march would