The answer should then be to get a better judgement of who is likely to become dictator, not to say "wait until they become dictator first." Like, if you really think they're going to be dictator, it would be best to stop them before they become one; it's harder to oppose a dictator once they fully control the government. It's for that reason that people say they would go back in time to kill Hitler. That's why I'm calling your argument silly.
Correct. I don't believe in killing people before they do anything wrong. I really can't believe people think that it is fine to kill innocent people because they may turn bad. There is also the possibility that you cause Hitler (see the Twilight Zone episode "Cradle of Darkness").