Yes, the US knows the exact amount their corporations are NOT paying taxes on. Just apply a tax and be done. Instead, they want to define what other countries will do, in order to fix the US tax leaks. I see this more as another attempt to control other countries than a real tax proposal.

How else do you solve this in the US?

Company A sells all of its IP to Ireland. They have the Irish company charge them 100% of the profits for IP. Poof. No US taxable income.

What's your magic beans solution for this beside what the IRS plans to do?

Could you walk us through your proposed solution? Like what the United States could be doing that would be a proper job of taxing its own corporations?

What does a proper job of taxing US corporations look like?

Currently, US corporations have a minimum tax of 10% on global income or 20% on US income; sounds like the numbers are proposed to change to 15% and 28% (or something; NYT paywall is loading too fast today, and it's a proposed law so the details aren't set and not worth fighting over); and the US is saying hey, these guys are going to pay 15% on income from your country, you may as well have them pay it to you instead.

The AMT on global income was part of the Trump tax changes, and is a departure from the full corporate rate on global income, but only due when/if money made it back to the US.

I imagine a next step would be charging multinationals headquartered elsewhere but operating in the US the AMT on their global income. That's kind of far reaching though, so if they can get a few major countries on board instead, that's better.