This selfishness if of course natural for any human, but that does not make it better.
It's the self justified "us" than do most damage, not some "others".
Any evidence for that?
Because again and again, humans are well-documented to NOT dance on each other's graves. We consistently pull back from the brink of destroying the "other" and not only let them live, but help them rebuild.
I'm not saying that war is not necessary, but pretending that you're fighting zombies thirsting for nothing but your blood is idiotic. The soldiers you're fighting joined their army to protect their people. The people itself most likely just want to passively continue with their life, not understanding what the war is about, knowing nothing but the date of the first bomb. The people that started the war is sitting somewhere cozy, out of reach.
Simply not true in the case of, say, an aggressor who initiates conflict by invading other countries.
Many a times there is definitely a right an wrong in war.
The side which is right has no choice but to respond with aggression. Fight, or else be laughably annihilated for the sake of a pacifist ideology.
And yet you demonstrate it yourself with, "I expect them to do it, but not us in the HN community. We're different here."