Most observers seem to think that the government lawyer tasked with defending Obamacare had a bad day yesterday. And I suppose that's true, since it's by definition tough to defend the indefensible. The conversation seemed to turn on the idea of enumerated powers. Everyone has long concluded that Justice Anthony Kennedy is the key vote and this observation seems crucial:
Kennedy: [H]ere the government is saying that the Federal Government has a duty to tell the individual citizen that it must act, and that is different from what we have in previous cases and that changes the relationship of the Federal Government to the individual in a very fundamental way.
This is the classic conservative argument on the matter. If the government can compel you, via an individual mandate, to buy a product or service, it can pretty much compel you to do anything. We've been headed for this moment for a long time, given the numerous ways that the federal government has used the Commerce Clause to regulate and control vast swaths of the overall economy. The indvidual mandate is the really the endgame of the argument; if it is constitutional, the federal government's power is absolute.