Not as many as you'd think. When America started going after foreign banks believed to be "hiding" or "sheltering" American dollars from American taxation, many foreign banks literally kicked out their American customers and refused to take any new American accounts.
You should know (if you don't already) that America is the ONLY COUNTRY IN THE WORLD that taxes its citizens no matter where they live OR WORK in the world.
I had an offer some years ago to EXPAT and do some work in the Netherlands and Belgium. Among the reasons I didn't do it: DOUBLE and in some cases TRIPLE taxation. I'd have to pay the taxes for each country I'd worked in PLUS because I'm an American, I'd have to pay America's confiscatory tax rates also.
We do in fact have the WORST taxation in the civilized world. We're the ONLY country that taxes it's citizens on all money made abroad. At least that's my understanding.
I think Eritrea does as well.
If you stay out of America for an extended time (one year, I think) then you don’t have to pay US taxes on earned wages.
Plenty of conservatives approve - they seem to think such laws enforce "economic patriotism."
Thats why I like it when people get away with screwing over the U. S. Govt. The IRS is more an enemy of the U. S. than ISIS.