Long story made too simplistically short: Reconstruction never had a chance. Lincoln's thoughts such as he had time to think about Reconstruction before his untimely death were hopelessly naive as were the peacekeeping efforts of Grant and others solving the disputed presidential election of 1876 effectively turning the South back over to the locals who were responsible for starting the war in the first place. It was time to send the troops on Southern soil back home because politically the occupation could no longer be sustained. The attempted Reconstruction though including the 13th, 14th, and 15th Amendments never had a chance. Fast forward to the modern civil rights movement starting in the 50's