Is America's waging war in Iraq in defiance of the word of God?

If Jesus said "turn the other cheek," "how you treat the least among you is how you treat me," "love thy neighbor," and "let he who has never sinned throw the first stone;" isn't waging war anywhere in direct defiance of these dictates? Did Jesus ever say there were exceptions to these directives? If not, why do so many Christians who name their religion for Jesus Christ and worship Him as God, support a war in Iraq that would be in direct contrast to His word? Serious replies only please.