With Roth, I do wonder sometimes. Roth was clever but after the hearings, how come he couldn't enlist allies and start a war against the Corleone Family?? How come he had to go on the run and were the Rosato Brothers killed? I mean after the attempt on his life and the murder of Johnny Ola, I would have tried to fight back. I don't think this was properly explained in the movie.
Good points and questions. I think the question originally asked in this thread should have been framed as threats to Michael, not to the Corleone Family. Mafia families do not go out of business. On the other hand, Dons come and go. Sollozzo was a threat to Vito and Roth was a threat to Michael.
