"War is a sociological safety valve that cleverly diverts popular hatred for the ruling classes into a happy occasion to mutilate or kill foreign enemies." -- Ernest Becker
War provides the perfect cover for those waging it to commit crimes against not only enemies but also friends. Amid the patriotic flag waving and somber ceremony, the populace is cowed into distraction and for the most part will not see the chicanery and manipulation that not only created the conditions FOR the war, but also will not perceive that the purpose OF it is not to defeat the enemy, but to financially castrate and sociologically neutralize those who are actually helping to wage the war.
Such is the process by which those in power consolidate their advantage among their so-called friends.
The Christian Crusades of millenia past provide an apt example of this deceptive process. With no enemies nearby and a surfeit of armed and affluent noblemen itching for aggressive acts, kings and ministers of past empires dreamed up external threats by which to distract their powerful friends from contemplating revolution. Jerusalem and the dark-skinned Muslim realms have always been a popular target. The subsequent conflicts not only reaped new riches for the warmaking kingdoms, but also depleted the ranks and resources of those sent to fight, thereby lessening the potential political threat to the very people who dreamed up the wars in the first place. Two birds with one stone.
Those innocents killed in such cynical gambits now bear the unfortunate title of collateral damage, regrettable but necessary sacrifices to the selfishness of those in positions of power who seek to maintain it. So this world full of greedy humans continues to turn.