The tax code already requires that income tax earned in the U.S. be taxed in the U.S. My father's job essentially involves making up the numbers. Why do I say

The tax code already requires that income tax earned in the U.S. be taxed in the U.S. My father's job essentially involves making up the numbers. Why do I say make up numbers? Often, corporations are multinational. Some part of the corporation makes a sale, but parts in two countries did the work. The rule is that the sale is allocated between the two parts as if they were two companies, and each part pays where it's located. But how much would the part that made the sale pay the other part if they really were two companies? Who knows? So they hire people to make up convincing numbers; they find other transactions between companies that actually are separate to compare to. As you might imagine, this leaves tons of wiggle room. In short, in this case, the reasonable thing is actually the law, but it gives companies plenty of room to take advantage.