The results of the bloodletting at Antietam were inconclusive. Robert E. Lee was forced to withdraw to the South, ending his first attempt to take the war to the North. But George B. McClellan, despite overwhelming superiority, was unable to score a knockout blow against the Army of Northern Virginia. The political consequences of Antietam were large, however. Abraham Lincoln used the victory as the occasion to announce his Emancipation Proclamation, effectively making the war for the Union also into a war against slavery. As well as radicalizing the Union’s war aims, the proclamation (which took effect on January 1, 1863), had the diplomatic result of making it impossible for European powers to recognize the Confederacy as a legitimate government. Militarily, Lincoln’s dissatisfaction with McClellan’s performance, including his nonresponsiveness during their October 1862 meeting, led to him being removed from his command in early November.