Enforcement. Getting billions out of intellectual property works better if you have a couple dozen aircraft carriers, etc. to back up the diplomats and trade treaties.

"You can get much farther with a kind word and a gun than you can with a kind word alone."

Why shouldn’t they? Google pays sales tax here too and yet have a corporate income tax given they are based in the US.

My point is why are they subject to a corporate income tax on income earned and already taxed abroad? The US government hasn't supported that income.

Without arguing for or against repatriation taxes, I don't think it is true that "The US government hasn't supported that income."