Now you know it is, here's a wikipedia page for you to learn more as it is a tenet of several religions and philosophical thinkers: https://en.wikipedia.org/wiki/Pacifism

I think it's as childish to discard this as it is to think it's "inevitable" to nuke people or to go to war. Everyone can have their own childish thoughts specially when I'm not in power or seeking a position where I have to make that hard choice, so I choose for me and I'll tell it to whoever asks.