"I have no doubt an attempt will be made to occupy Fredericksburg and use it as a base of operations against Richmond. Our present force there is very small, and cannot be re-enforced except by weakening other corps. If you can use General Ewell's division in an attack on General Banks, and to drive him back, it will prove a great relief to the pressure on Fredericksburg; but if you should find General Banks too strong to be approached, arid your object is to hold General Ewell in supporting distance to your column, he may be of more importance at this time between Fredericksburg and Richmond. I do not know whether your column alone will be able to hold Banks in check and prevent his advance up the valley; but if it will, and there is no immediate use for General Ewells command with yours."The aggressive Jackson jumped at the opportunity to attack. He was sure with Ewell's troops that he could crush Fremont or Banks. It was decided that Ewell would secretly replace Jackson's men threatening Banks at Swift Run Gap, while Jackson moved to join Johnson and defeat an insulated part of Fremont's army, which was preparing to join Banks. Although the Federal forces greatly outnumbered the Confederates, if the Confederates could combine two armies against one Union force, they could get the superior numbers on the field. That is just what Jackson was planning to do by marching to join Allegheny Johnson in the Blue Ridge Mountains.