The reality is that the atom bomb made the world safe for Chairman Mao and Josef Stalin - two of the most bloodthirsty individuals on the earth, who slaughtered far more people than Hitler did. Their blood be on your hands, you freaking win-at-any-cost lunatics.
That's only because Josef Stalin managed to get his
hands on the atom bomb.
Using atomic bombs on Germany, say, after it invaded the Sudetenland, would have saved the lives of innocent people in Czechoslovakia, in addition to Poland and France and so on. The people of Czechoslovakia, Poland, Belgium, and so on were not to blame for Hitler's decision to commit aggression. They therefore were under no obligation, none whatsoever, to endure one single casualty as the result of the decision of the German government to attack them.
They had every right to just push a button and make the whole problem go away if they could.
It would be nice if that button would summon angels who would just take all the Nazis away, and any German soldier who tried to use a weapon in aggression. In the real world, though, we often have to settle for less.
Ultimately, the safety of the German people is the responsibility of the German government. Other people will first take care of their own safety before trying to feed the Germans at their own expense, say, if their crops failed. Just as a bad harvest in Germany doesn't create an obligation on the part of the rest of the world to, at their own cost, feed the German people - even though we might think it nice of them if they did pitch in - so a bad government in Germany doesn't create an obligation on the part of the rest of the world to endure getting shot at in order to reduce German civilian casualties.
Basically, no one gets to get away with making a nuisance of himself. If peaceful people see soldiers with guns coming to their village to disturb them, they have the right both to stop those soldiers - and make sure there are no more coming from wherever it is they came from.
In order to eliminate any possibility that Germany could send any more soldiers marching outside its borders to shoot at people, and to do it from a distance so as not to expose a single one of your own people to enemy fire, it is probably going to be necessary to use clumsy means. But if we aren't obligated to feed the hungry at our own expense, why are we obligated to put our lives at risk to make things easier on the victims of a bad government?