Call it white guilt if you must (though it's really a misnomer), but the fact that Americans are aware of their own racism makes the situation much, much more tolerable than in other places.
Sure, covert racism is still a problem (a big one at that), but at least there is awareness and a substantial degree of introspection. Both of these are absent in more racially homogenous countries, where not only is racism overt, but there is so little public consciousness of it that extreme racism is accepted as a matter of course.
In the US the words "oh good, you're not dating a black girl" will be outright rejected as racist, or at least give people pause and cause discomfort. I've personally experienced the exact same statement tossed around in another country as if it was the most natural thing to say in the world.