The money is taxed when individuals finally get it, assuming they are US residents or citizens and earn above the minimums required to pay taxes. Corporations don't need to pay taxes at all in theory; it just double-taxes the same income and leads to the govt adjusting rates accordingly to achieve the same outcome (e.g., avoid driving corporations overseas with an uncompetitive high tax regime, which the US currently has).
The GDP of the US last year was less than 21 trillion, and we're talking about fraud that's allegedly 400 billion. Ergo, we're talking about ~2% of GDP. That's not "chasing pennies."
To put that in different context, 400 Billion is about 4x as much as the federal government spends on education. It is about 15x what we spend on energy infrastructure.
400 billion is a 2% of GDP but >10% of the federal budget.
