About 11.5% of global GDP is hidden in offshore accounts, amounting to $8.7T, and unpaid taxes to the US would amount to $170B in 2016 alone. Another $70B avoided by companies, so around a quarter trillion dollars per years in net new missing taxes per year. Given that's less than the current deficit, it makes what I said unlikely, although depending how many years it's been going on that's a big piggy bank. I'll see if I can dig up what I was initially thinking, but I could have just mis-remembered.

[1] https://www.bostonglobe.com/ideas/2018/01/20/trillions-dolla...