Europe was ripe for war. What if a different leader with different war plans (I.e. Leave Russia alone) led to a more protracted war. Or worse, an axis alliance with Russia. This scenario could have the potential of leading to more deaths. How many died in WWI without a Hitler?<quoted text>
Maybe I did and maybe I didn't.
In this case "the devil you know" definitely killed several million people.
In terms of a gamble, the gamble would be that the results (of killing young Hitler) would not be worse than that.
That might be a fair gamble, for mankind, though not necessary any specific person or family.
I mean, seriously, what are the chances that killing him could make things worse?
That's just one of many possibilities. Some with good outcomes. some not so good. Do you really want to take that chance? I say, let the past be, and focus on the present and future.