I would answer 6. Other: George McClellan. Here's an article that gives a brief introduction to the background of the attacks on McClellan and that then gives links to online pro-McClellan books and articles:
GeorgeM wrote: I got my Porters mixed up. I was thinking of Fitz John Porter.
Fitz John Porter's case is a good example of how dishonest and vicious Lincoln and the Radical Republicans could be. After the disaster at the Battle of Second Bull Run, General Pope, looking for a scapegoat for his own failures, falsely accused Porter of dereliction of duty and cowardice. Porter's court martial was rigged and he was kicked out of the army. Years later, long after the war, the Schofield Commission reviewed Porter's case and concluded that his court martial was completely unjustified and that, far from performing poorly at the battle, Porter performed well and in fact kept the defeat from being worse than it could have been.
An eye-opening examination of Porter's case is presented in Otto Eisenschiml's book The Celebrated Case of Fitz John Porter: An American Dreyfus Affair.