To effect this, Lee again played upon the nervous apprehension felt in Washington for the safety of that city. He detached Jackson, and sent him to the Rappahannock to threaten Pope, while remaining within reach of Richmond in case of need. This movement increased the apprehension in Washington, and a considerable part of McClellan's force was withdrawn by water. Thereupon Lee sent another corps to the Rappahannock, a proceeding which led to the withdrawal of pretty nearly all that remained of McClellan's army, to reinforce Pope, and the abandonment of the campaign by way of the peninsula. Lee instantly transferred the remainder of his army to the Rappahannock, leaving only a small garrison in the works at Richmond. Pope was alert to meet Lee at every point, and he was being strengthened by daily reinforcements from what had been McClellan's army. But in Pope, with all his energy and dash and extraordinary self-confidence, the Federal government had not found a leader capable of playing the great war game on equal terms with Robert E. Lee. Grant and Sherman were still in subordinate commands at the West, while Halleck, who believed in neither of them, had been brought to Washington and placed in supreme control of all the Union armies. Lee quickly proved himself greatly more than a match for Pope in the art of war. Making a brave show of intending to force his way across the river at a point where Pope could easily hold his own, Lee detached Jackson and sent him around Bull Run Mountains and through Thoroughfare Gap to fall upon his adversary's base at Manassas. As soon as Jackson was well on his way, Lee sent other forces to join him, while still keeping up his pretence of a purpose to force a crossing. It was not until the head of Jackson's column appeared near Manassas that Pope suspected his adversary's purpose. He then hastily fell back from the river, and concentrated all his forces at Manassas, while Lee, with equal haste, moved, with the rest of his army, to join Jackson. His strategy had completely succeeded, and he promptly assailed Pope, with his entire force, on the very field where the first great battle of the war had been fought, a little more than a year before. Pope struggled desperately, but after two days of battle, he was completely beaten and forced to take refuge behind the defences of Washington.