Who Slapped Clinton?

Bill Clinton, George Bush, a spectacular looking blonde, and a frightfully awful looking fat lady were in a train carriage. After several minutes of the trip, the train passes through a dark tunnel, and the unmistakable sound of a slap is heard.
When they leave the tunnel, Clinton has a big red slap mark on his cheek.
The blonde thought, 'that rascal Clinton wanted to touch me and by mistake he must have put his hand on the fat lady, who in turn must have slapped his face.'
The fat lady thought, 'that dirty old Bill Clinton laid his hands on the blonde and she smacked him.'
Bill Clinton thought, 'George put his hand on that blonde and by mistake she slapped me.'
George Bush thought, 'I hope there's another tunnel soon so I can smack Clinton again.'