Sunday's Washington Post features a front-page story examining the notorious temper of Sen. John McCain, including a first-hand account of McCain's physical altercation with fellow GOP Sen. Chuck Grassley.

It was early 1992, and the occasion was an informal gathering of a select committee investigating lingering issues about Vietnam War prisoners and those missing in action, most notably whether any American servicemen were still being held by the Vietnamese. It is unclear precisely what issue set off McCain that day. But at some point, he mocked Grassley to his face and used a profanity to describe him. Grassley stood and, according to two participants at the meeting, told McCain, "I don't have to take this. I think you should apologize."