Levying additional taxes involves a simple principle: go where the money is. Since money has been increasingly going to the top, that’s where additional tax revenues have to come from. It’s really that simple. It used to be said that the top didn’t have enough money to fill the hole in the deficit; but that’s becoming less and less true. With those in the top 1 percent getting more than 20 percent of the nation’s income, an incremental 10 percent tax on their income (without loopholes) would generate revenues equal to some 2 percent of the nation’s GDP.