I don’t think Buddhism teaches just war. Saint Augustine brought the just war theory to Christianity, Jesus spoke against violence. The Japanese Zen Buddhist somehow decided the enemy had very bad Karma and they were just part of their karmic debt. Losing their heads may have helped the reconciliation. If a Tiger is going to kill someone I believe it is permissible to save them, and stop the Tiger from more bad Karma, and kill the sucker. The Tibetans went out to meet the invading Chinese with guns. In this instance I believe the Chinese was the Tiger. It proved true. I don’t believe Buddhism allows for war, peace must start somewhere, and throwing down your gun facing imminent death is a good start. Man can reason and justify anything, as mindful Buddhist I think we should see through it. Peace.