TigerHawk explains the basis for this phenomenon.

Here is a sample:

We Americans are quite used to being accused of human rights violations by every dirtbag — and every apologist for dirtbags — on the planet. Activist American leftists and their anti-American supporters abroad have been accusing America of atrocities at least since the mid-sixties. According to the left, the United States and its soldiers or agents were criminals by virtue of our dealings in Vietnam, Laos, Cambodia, Chile, Cuba, El Salvador, Nicaragua, Venezuela, Israel, Iraq, Egypt, Saudi Arabia, South Africa, Angola, Somalia and Ethiopia (I’m sure that I’ve forgotten a few). We know that wherever we go, whatever we do, we will be committing human rights violations — at least according to international NGOs, the BBC, most European media, most American professors, most activists in the Democratic party, and most members of the United Nations. …

I will start caring what the world’s chattering classes think when they hold non-Americans — Africans, Arabs, and Chinese in particular — to the same standards. Until they do, I am forced to conclude that these critics of America are either racist to the core — they simply expect less of Africans, Arabs and Asians — or politically anti-American. There is no third explanation. Until then, therefore, I will support our military, knowing full well that the world has never seen a serious war without some violations of law, and that this war is almost certainly the cleanest counterinsurgency since the invention of counterinsurgency.

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