Ah, the American public. God love 'em. The Economist asked if they'd rather tackle the federal deficit by cutting spending or raising taxes, and the runaway winner was cutting spending, by a margin of 62% to 5%. So what are we willing to cut? Answer: pretty much nothing.
via Cutting the Deficit – Mother Jones. Add up everything that even a quarter of the population is willing to cut and you wind up with under 5% of the federal budget.