It's not even close, either. Reason just had a highly illuminating graph about this phenomenon. It listed how much each sector of the federal government spent, and the willingness of the public to cut spending in each sector. Foreign aid was the only area in which a clear majority supported significant cuts, and it was easily the sector with the LEAST spent each year. Cutting military spending was actually more popular than I would have imagined, so that would be the first I would target, given what a big chunk it is. Entitlements are the purality, though, and they are the elephant in the room. At some point in the near future, they will need to be addressed. And that means cut, hopefully.