Because it was in his nature to be cautious and skeptical, GEN Hooker did exactly what Lee expected. He watched and waited. This gave Ewell time to cross the Mason-Dixon Line. It wasn’t until his spies and scouts reported that Lee, himself, had crossed the river that Hooker felt compelled to move. He had fully expected that the movement north was a feint and that Lee was going to try to dash south and east and attempt to place his army once more between Hooker and Richmond. But now he saw that that was in error; Lee was going north but where to?
Because the Army of the Potomac was positioned in depth with units staggered behind one another, Hooker had the advantage of using a number of crossing points when he finally gave the order to move north to trail Lee.
Back in WASHDC, Lincoln and GEN Halleck, his senior Army Commander, could also read a map. It was clear that Lee was using the South Mountain as a screen. But this also funneled him to only one point: the town of Chambersburg. From there he had some options but the logical one was to move east and north. At this point, Westminster became the city of vital importance. It was a major crossroads and the terminus of a rail line that ran directly from Baltimore some 20 miles away. Halleck immediately gave orders to begin to concentrate vital supplies there. They’d be waiting when the Union army arrived. Whatever Lee’s objective was, Westminster would play a key role.
By 28 June, Lee was deep into northern territory. Ewell was threatening the supply depot at Carlisle – a place he had once been stationed. Union forces were at least a day’s march behind.
