Vietnam really hurts my opinion of him. Either way, it's hard to deny that he was an unlikeable turd.
I actually like LBJ as a person a lot. It's clear that he could be very mean and ruthless to people, and it would be very difficult to be a member of his staff. But the man was such a colorful character, crudities and all, that I find him very likable. I guess it's probably easier to like him from a distance than it would be close up. He once urinated on one of his own secret service agents! But it should be noted that those who worked with him said that his abuse of people was not the sum total of him. Many things he did, like inviting people into the bathroom, his many sexual conquests, and his ensuring that everyone in his family had the initials "LBJ" (even his two dogs were named Little Beagle Johnson and Little Beagle Junior) actually make me like him more because they make him seem like a very genuine, human person.