I have to somewhat agree with Malacasta (I know. Shocking!)

I think the reason is because we want to feel good about ourselves as human beings. In all countries we're willing to find excuses, find reasonings for the things we disagree with because if we, in our own individual countries, don't feel something is right, then we either have to step up and see about changing it, or we have to accept that we're too weak in mortal character/ability to bring about the change we want to see in the world.

It diminishes our sense of self to believe we live in a country capable of doing wrong beyond a certain extent.