It's only easy to dodge them due to the current rules of accounting - we can work on fixing that component or enforcing minimal VAT taxes down-chain. For instance the US could require that a VAT of at least 20% be paid before reaching the US, then collect any taxes left on the table by, say, the bahamas when they only collect a 2% VAT - the US could gate goods entry based on a 18% fee on the difference.

This applies only to actual goods value (and doesn't look at capturing out-of-band transactions like online orders of virtual goods) but it's a really dead simple and easy to enforce law that'd kill a lot of tax dodging dead.

The real issue isn't that it's hard to tax these companies - it's that there isn't a significant political will in taxing these companies.