This is certainly an issue to be discussed and addressed, but the headline, directly from the article, is incorrect, re: "$2.1T in unpaid tax":

> In total, US multinationals are sitting on an estimated $2.1tn in untaxed offshore profit...

US corporate taxes on $2.1T are @ least 65% less than the $2.1T profit, itself. The correct title would phrase it as "unpaid taxes on $2.1T".