It is clear from this and other sources that Kerry committed war crimes in VietNam. He was a loose cannon, shot randomly at civilians, burned down a village, etc.
He projected his guilt on his "beloved" band of brothers and the entire military chain of command, either to assuage his guilty conscience or distract from his crimes.
So Kerry was either a mentally disturbed man who could not tell truth from fiction, or a deliberate liar manipulating public opinion for his own benefit.
Either way, he is "Unfit for Command."