(I'm not a tax attorney) Most of those countries have double taxation agreements with the US. You can take a credit or deduction for taxes paid.
In general, if you're a US citizen, you pay the maximum of US or foreign taxes. Usually you end up paying mainly foreign tax, since most (worthwhile to live in) countries tax individual income higher than the USA does. There's also a ~95k income exemption if you're out of the USA.
If you move to a zero or low income tax place, then the global taxing power of the US becomes relevant. Still, you don't pay higher taxes than if you remained in the USA.
Taxes probably shouldn't be a major factor for a US citizen in deciding to expatriate. If you want to live in Sweden more than the US, and can get a job, go for it. You don't have to go forever. I think the only issue is that you might not end up paying enough Social Security tax to the US to earn the maximum amount, but for someone paid like a tech worker, not an issue.
The other thing is if you move to a place with lower cost of living, you might have lower wages for the same quality of life, which means lower taxes paid (in absolute rate, and in progressive tax tier).
I don't think there's a better place to do a tech startup than Silicon Valley now, but if you want to do a wind or solar energy startup, moving to Germany might make sense. If you want to go SCUBA diving a lot, move to Malaysia or Australia and put up with worse jobs.
Taxes really shouldn't be the primary reason why you do anything.
What if the low tax country had low tax because it had low government spending on benefits, etc. You'd still have to pay US tax rates for little benefit.
You would still have the us foreign exclusion, at least. But most of the low tax places are not places I'd want to live (which is sad, as a libertarian); I've lived in several of them. Hong Kong is the sole exception, and there the benefits (at least roads, security, etc) are superior to the USA, due to high density and efficiency and a long period of good governance.
(also, most of the benefits of living in a high tax high service economy are not really delivered by the US government now, even given moderately high taxes. Defense spending is not particularly improving my quality of life, and to the extent it does, it is a global value which taxpayers in Japan benefit from as well. I'm not sure why the US Government and California are relatively less efficient at delivering worthwhile services than other governments around the world.)
In general, if you're a US citizen, you pay the maximum of US or foreign taxes. Usually you end up paying mainly foreign tax, since most (worthwhile to live in) countries tax individual income higher than the USA does. There's also a ~95k income exemption if you're out of the USA.
If you move to a zero or low income tax place, then the global taxing power of the US becomes relevant. Still, you don't pay higher taxes than if you remained in the USA.
Taxes probably shouldn't be a major factor for a US citizen in deciding to expatriate. If you want to live in Sweden more than the US, and can get a job, go for it. You don't have to go forever. I think the only issue is that you might not end up paying enough Social Security tax to the US to earn the maximum amount, but for someone paid like a tech worker, not an issue.
The other thing is if you move to a place with lower cost of living, you might have lower wages for the same quality of life, which means lower taxes paid (in absolute rate, and in progressive tax tier).
I don't think there's a better place to do a tech startup than Silicon Valley now, but if you want to do a wind or solar energy startup, moving to Germany might make sense. If you want to go SCUBA diving a lot, move to Malaysia or Australia and put up with worse jobs.
Taxes really shouldn't be the primary reason why you do anything.