If you woke up this morning and asked yourself, “Would conservative podcaster Ben Shapiro travel backwards through kill and murder Adolf Hitler when Hitler was a tiny baby?”, then (a) you should seek help but (b) I have an answer to your question: Shapiro would not kill Baby Hitler, as he explained to a presumably confused crowd at the anti-abortion March for Life: Ben Shapiro at March for Life: “The truth is no pro-life person would kill baby Hitler. We asked @nytmag readers: If you could go back and kill Hitler as a baby, would you do it? Assume that going back in time merely eliminates Hitler, and that the sole effect of that is that the Nazi Party lacks a charismatic leader and never takes power in Germany, and World War II and the Holocaust are averted, and nothing worse than World War II transpires in this alternate reality, and there are no unintended negative consequences of time travel. Take, for instance, the most famous time travel problem, the grandfather paradox: Suppose you go back in time and kill your grandfather before your mother/father has been conceived. In “Cradle of Darkness,” an episode of the 2002-’03 reboot of the Twilight Zone, Katherine Heigl’s character is sent back in time to kill baby Hitler. She succeeds — but Hitler’s mother adopts another baby and raises it as Adolf, who grows up to lead the Nazi Party, start World War II, carry out the Holocaust, etc. Hitler survives, identifies the force trying to kill him as Jewish, and becomes a vociferous anti-Semite, setting the Nazi rise to power and the Holocaust into motion. These aren’t very satisfying versions of Hitler-killing time travel. But they’re versions that obey the Novikov self-consistency principle, and thus make considerably more internal sense than versions in which you really can go back in time and kill the actual Hitler. Can we have any sense of what the ramifications of killing Hitler would be? Let’s get ourselves out of this thicket, then, by supposing instead that no time traveling takes place and instead we’re an Austrian living in the town of Braunau am Inn in 1889 who has a strong premonition that the wee baby Adolf is going to grow up to kill tens of millions of people, and we are thus driven to kill him. For one thing, baked into the premise of this question is the idea that the Nazis would not have risen to power, launched World War II, and carried out the Holocaust were it not for the existence of Adolf Hitler. And unless we have answers on that, we can’t know the consequences of killing Hitler and thus whether killing Hitler did more good than harm. If we can’t know if killing Hitler is right or wrong, can we know if anything is right or wrong? In his classic 2000 paper “Consequentialism and Cluelessness,” the University of Sheffield’s James Lenman explained the issue using the case of a German bandit in the year 100 BCE attempting to decide whether to kill a distant ancestor of — you guessed it — Adolf Hitler: We just don’t know what the consequences of killing Hitler would’ve been at any point.
Source: The philosophical problem of killing baby Hitler, explained