Why we do it

A series of articles called "Our Nation's Soul Sickness" by Roberto Rodriguez explains some things:

American Indian scholar, Jack Forbes writes about a disease that afflicts the West, an illness he refers to as: soul sickness. It's the belief that God has especially chosen Westerners to bring civilization and enlightenment to the rest of the world. While it permeates all of Western society, it appears to manifest most poignantly in the United States.
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Under this superstitious belief system, Westerners have been authorized by God to eliminate infidels and heathens if they don't convert (because if they don't, the unbelievers may wipe out the civilized world). This traditionally has meant the right to take lands, colonize and enslave peoples and the right to invade, occupy and destroy nations. It matters little if one innocent person dies or a million, because they are not truly human. Conversely, the death of one Westerner or the threat to one, is "just cause" for war. Since Westerners believe God has anointed them to spread Judeo-Christian values, democracy & capitalism, all their military incursions are justified. This is why war is constantly waged, always obviating the need for laws and trials.
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Accompanying these delusional ideas is the belief in the eternal right – with impunity – to freely exploit these nations, their peoples and resources.

The question before is this: do we have the humility, as a people, to see this sickness for what it is and to reject it?