According to Forbes, there are ~500 billionaires in the U.S., with an average wealth of ~$4B. Let's say $2T total. If you assume they can make 10% annually on

According to Forbes, there are ~500 billionaires in the U.S., with an average wealth of ~$4B. Let's say $2T total. If you assume they can make 10% annually on that wealth (probably optimistic), that's $200B/year. It is totally implausible given the history of U.S. tax policy and compliance, but let's say you could capture a 50% effective rate of that. That's $100B/year: Not even half the increase in U.S. tax revenue between 2013 and 2014 due to economic growth[1]. Did that extra $200B enable Congress and the President to solve significant problems last year? [1] And whether you believe in the Laffer curve or not, it's hard to imagine that levying a massive tax on billionaires' investment income would have a positive effect on economic growth & thus tax revenue from the non-super-rich.