Keep in mind, Taxing the rich more will simply make them want to leave the country.
It's a good thing income is taxed abroad, then.
I didn't know income was taxed abroad. That's fine then.
Only above around $100k and it's easier to find tax avoidance loopholes in a world with a globalised economy but an insufficient regulatory framework to match. However, it is one of the reasons that "They'll move abroad," carries a lot less weight in the US.
Theoretically, they could surrender their US citizenship to avoid US tax. But, yes, most people wouldn't want to do that.