But as a person from the future that crime has been commited. And as for me if I were going to murder people on a world wide scale then yes I would desreve to be taken out before I did it. Also I dont think you can compare what Hitler did to crime, what he did goes way beyond any crime.  How could I live with myself if I went back to 1926 and seen Adolf Hitler standing there on a Berlin street, an easy target, and not take the shot? How could I open the history books and not feel somewhat responsible?

... from an ethics perspective.  It's my understanding that it would not be right to kill Hitler ... he had not yet done these atrocities you can't punish him, even if you know he was going to do them later on.  ...it's an interesting ethical decision to ponder.

So is this one; we developed the atomic bomb, a device that we think can save many thousands of lives, on both sides, and shorten the war if we use it and get Japan to surrender sooner... by the above logic we shouldn't use it because we don't know for sure that Japan will fight on (costing those lives) if we don't use the bomb and so, otherwise innocent people will die. This was the crux of a debate I witnessed years ago between a fellow that was the tail-gunner on the plane that escorted the Enola Gay on her trip to Hiroshima (anti-bomb) and a fellow that was an aide to on of the higher-ups on the invasion project andactually saw the mock-ups of the invasion, quite by accident (pro-bomb)... how many of us wouldn't be us if the bomb hadn't been used?WallyPS

As he would be from the future he would know; if Hitler lives it is his fault.W

I guess I'm just being stubbornly thick headed because I interpret the question differently.If from the future and you did know what Hitler was going to do, then yes.The atomic bomb was justified ONLY in that it stopped the war.Quick question concerning the present.  Would it be morally justified to assasinate Chavez or Ahmadinejad right now?  My answer is a resounding YES.

They've made and are threats, and are actively seeking ways to become more a threat. Stumpfoot, I viewed the question as "going back in time but not yet realizing what Hitler would become". I answered it as "Hitler hasn't done anything threatening yet"

At least everybody knows who Adolf H. is. If you could travelled through time and erased him, then someone else, unknown so far, might probably have replaced our Adolf H.  And this new Fuhrer might have realised worse or less mistaken plans than Adolf's ones. Meaning that today you might be swearing fealty to "our beloved Fuhrer" ! (Or we wouldn't debate here at all)