I can't get over the fact that America nuked Japan during WWII, twice. One for each world war, I guess. I can't imagine rationalizing something so destructive and generally wrong for humankind. I just can't get over it.
And don't be fooled by the seemingly amicable relationship we share with Japan now. They have gotten us back, they just haven't been so obvious about it. We filled their land with radiation and jeopardized their gene pool with nuclear arms. They did it to us by introducing Nintendo.