This kind of assumes liquidity... A lot of wealth is tied up in stocks and physical assets. Imagine having to orchestrate selling 2% of everything you own every year. And why over a billion, why not put it at over a million, or ten?<p>You could seize the full assets of every US Billionaire and it wouldn't cover a single year of the federal budget or dent the debt. There's no way to tax out of this hole... spending cuts need to happen, and restructuring as well. Taxes should focus on points of exchange.