Antietam enabled the Union to repel the first Confederate invasion of the North, The battle allowed Abraham Lincoln to issue the Emancipation Proclamation, Antietam kept Britain and France on the sidelines, The battle lifted sagging Union morale, Photographs from Antietam brought the horror of war to Americans for the first time, The battle may have saved Lincoln from a resounding defeat in midterm elections, Antietam marked the beginning of the end for General George McClellan.