In that interview with Brian Williams last week, he said when he gets to heaven he hopes he'll learn the answer to this mystery: John Kennedy once asked him to go back to the White House with him in the presidential limousine. He wanted to talk with Billy. Billy had a bad cold, and declined, thinking it would be very bad to get germs all over the leader of the free world. He asked for a raincheck, which JFK agreed to. Kennedy was assassinated shortly thereafter. This lost opportunity has weighed on Billy's mind for 42 years. It may be a clue to his tolerance of Bill & Hillary. That, and being a gentleman.