OK, educate me.... Is the reason that forced health insurance is unconstitutional and forced automobile insurance is not based on who is doing the forcing? State vs Fed?
The fact that you only need auto liability insurance if you own a car is part of the argument; however, the state vs. federal government is perhaps a more important (and probably less understood) part of the argument here.
We have a federal form of government, meaning that power is divided between state governments and the federal government. By ratifying the Constitution, the states ceded some of their power to the newly-created federal government. The federal government is one of limited power--its powers are limited to those powers granted to it in the Constitution. In other words, for the federal government to do anything, it must find a basis for that action in the Constitution.
Most of these powers are in Article I, Section 8. Among these powers is the power to regulate commerce among the several states. This power, called the commerce clause, is the basis for all sorts of federal laws. Congress has used this power quite widely, and the courts have generally interpreted it quite broadly, allowing Congress to regulate anything that has any connection with commerce. (Conservatives will argue, with some merit, that Congress and the courts have gone way too far in what they'll allow under the commerce clause. But, regardless, the commerce clause has been used as the basis for lots of federal laws, and that isn't going to change any time soon.) The commerce clause (as interpreted by the Supreme Court) clearly gives the federal government the power to regulate the health insurance industry. However, the question here is whether it gives Congress the power to require individuals to buy health insurance. At least one court has said that it does not.
State governments, however, have no such limits on their powers. States do not have to point to a provision granting them the power to pass a law. So, a state can require its residents to buy insurance. Of course, there are limits on states' powers. States cannot pass laws that violate people's federal constitutional rights. (For example, a state can't require people to go to church, or as the Supreme Court recently held in a case out of Chicago, a state (or locality) cannot prohibit gun ownership.) Another significant limit on state's powers is that, if a state's law conflicts with federal law, then federal law trumps the state law (Article VI of the Constitution).
So, in conclusion, the federal government's power to regulate people's behavior must be rooted in a power granted to the federal government in the Constitution. No such limitation on power applies to the states.
