Equally, the argument could be made to prevent the birth of those creating situations where the "lives of countless others" needed to be saved. I've always found this particular "what if" anti-abortion argument to be a pointlessly ludicrous. The only answers are circular reasoning. Yeah… it might have been terrible if Churchill had never been born. But, his firm leadership might not have been needed if Hitler hadn't been born. Neither reality is what we have. Neither argument has any real validity because the all the myriad conditions which bred both men an events still remain to raise up some other names in the same dichotomies.