Explanation: After the US Civil War, fought over the issue of slavery, there was an immense appetite in the anti-slavery North for forcibly reforming the pro-slavery South during "Reconstruction", the period of military occupation following the Civil War.

The assassination of President Abraham Lincoln, however, led to Andrew Johnson succeeding him. Andrew Johnson was a blatant white supremacist who was opposed to effectively all measures to reform the South. Johnson would fail miserably when he actually had to run in an election a few years later, but the damage had been done - Reconstruction efforts were immensely damaged by the support for the planter aristocracy by the highest office in the land.