I agree, but I also think this is cherry picked. There are countries that are quite monoethnical that are doing quite well eg. Switzerland and Japan. Also I don't think USA is such a great place to live, even if it where the "worlds #1 superpower, whatever that means". Great military doesn't make a country nice to live in. Switzerland and France are much better in my opinion.
The US does not have a final deposit for nuclear waste. But nuclear waste is not more dangerous than other chemical waste which already has final deposits in Germany. The specifications are deliberately made harder for nuclear because of politics.