You'll see every major company in the world immediately relocate to the US..
No, you won't.
What bizarre world do you people live in, anyway?
Ali Baba will remain a Chinese company. ICBC will remain a Chinese company. China Construction Bank will remain a Chinese company. Agricultural Bank of China will remain a Chinese company. Bank of China will remain a Chinese company. PetroChina will remain a Chinese company. So will every other Chinese company. Fully half of the top 10 of the Forbes 2000 list will not EVER become American companies.
Royal Dutch Shell will remain a Dutch company. Toyota Motor (Forbes says their name has no 's' on the end. Who knew..) will remain a Japanese company. HSBC Holdings will remain a British company. BP will remain a British company. Volkswagen Group will remain a German company. Gazprom will remain a Russian company. Samsung will remain a Korean company. We're now through a majority of the top 20 with absolutely zero chance of relocating to the US, regardless of US tax policy.
That's just the publicly traded companies. Saudi Aramco will stay in Saudi Arabia. They own that government. They ARE that government. The LEGO Group will stay in Denmark. Etc.
When you get right down to it, it's mostly only US corporations that are sociopathic bastards. Many large foreign companies identify with their own nationality and explicitly support it. Do you really think Royal Bank of Canada (55th ranked in the Forbes 2000) is going to incorporate in the US? Really? Don't be ridiculous.
Your back of the envelope calculation is worth spit. A zero US corporate tax rate would simply rob our budget of billions. Billions that, whether or not they are necessary, are already spent, so we'd damn well better not cripple our ability to pay back the loans.