I had read several years ago--I guess it was probably in the Evan THomas book-- that Bobby Kennedy assumed it was a larger conspiracy. He also thought he was partly to blame--that it was tied to either his own investigations of the Mafia and the Teamsters, or retaliation for the covert attempts to assassinate Castro ("Operation Mongoose").
That doesn't mean he was right of course. He was completely devastated, didn't bring up his brother's death in public for five years. But I didn't know so many other people agreed with him. I mean, Gary Hart is not some wild eyed conspiracy theorist and does not have a personal stake in this.
