Just thought of a better analogy, I think.
In WWII the Nazis intentionally killed millions of children in their camps and elsewhere.
Meanwhile the Allies killed hundreds of thousands, possibly a million or more, in bombing attacks on nuclear and conventional German and Japanese cities and otherwise. Now I happen to think many of these attacks were not fully justified morally, but I hope you will agree there is a difference in the degree of moral culpability.
That should of course be “nuclear and conventional bombing attacks.”