"Though force in itself is an evil, when employed against a greater evil, the lesser of the two evils becomes in this world of relativity an act of righteousness. But this is not a free license to resort to force or retaliation."
"For example, there is a great difference between a righteous and an unrighteous war. A country may be purposely agressive and foment wars to satisfy its greed; a war so motivated is unrighteous action by the aggressors and no soldier should cooperate with it. To defend one's country against the aggression of another, however-protecting innocent, helpless people and preserving thier noble ideals and freedom-is righteous duty." Swami Paramahansa Yogananda in the Bhagavad Gita.
