[pc86]

I don't think you understand how taxes work. US tax rates are marginal, so for your effective tax rate to be 30% you'd probably be earning several million dollars in payroll. Very unlikely. Not to mention the fact that if you're an expat, income tax paid in your country of residence counts toward your US tax obligation.

If you live somewhere with higher taxes, you owe the US nothing. If you live somewhere with lower taxes, you owe only the difference.