John McCain has something of a reputation for never being more than two clicks away from erupting into a horrifying, dark rage. It's a theme you may have picked up on when reports of his saying some not very nice things to his wife surfaced a few months back. A new chapter of this time-honored storyline has been offered this week by Senator (and noted McCain enemy) Thad Cochran (R-MS), who recalled a congressional trip to Nicaragua in 1987 in which McCain allegedly went buck wild on a member of the country's communist regime during a meeting.

According to Cochran, "John had reached over and grabbed this guy by the shirt collar and had snatched him up like he was throwing him up out of the chair to tell him what he thought about him."

This would be an enjoyable anecdote for everyone if McCain were winding down his career playing poker in the cloakroom like most senators his age. But it's bad juju for a presidential candidate already plagued with a reputation for being an unstable rageaholic.

McCain quickly denied that the alleged incident took place, as has a former aide who accompanied him on the trip, but it's inevitable that this hothead motif will build steadily into a tiresome crescendo sometime this fall. We'll mostly be interested to see how long it takes for the serious news people to start really drilling down into the time McCain went to juvenile court for telling two girls to "stick it up your ass".