The Obama administration has never offered a principled explanation of how to square the health-care law's individual mandate with the Constitution. If Congress can force us to buy health insurance, what can't it order us to buy?
The US Supreme Court today heard arguments today on what may be the most important constitutional case in a generation. Some of the nation's top attorneys are debating the Patient Protection and Affordable Care Act, often known as Obamacare.
The eventual ruling could chart the boundaries of federal power for generations to come - not only for health care, but across the policy spectrum.
A major focus of the Supreme Court hearings is the individual mandate - the law's requirement that almost all Americans who aren't covered by employers must purchase a health-care plan, whether they want to or not.
The plaintiffs - including 26 states as well as individuals and businesses - argue that Congress has no authority to force people to buy insurance. Most Americans agree: A recent Gallup poll found that 72 percent - including 56 percent of Democrats - consider the mandate unconstitutional.
Obama administration attorneys counter that Article I, Section 8 of the Constitution, known as "the commerce clause" - giving Congress power to "regulate commerce among the several states" - is more than expansive enough to validate the mandate.
They rely on a list of Supreme Court precedents that stretch the definition of "interstate commerce" pretty far.
In the 1940s, the court allowed Congress to punish a farmer for growing wheat on his own land for his own use, on the theory that wheat prices would be affected if everyone did that. In the 1960s, the court classified civil rights laws as "regulations of commerce" even when they involved businesses that did practically no interstate business. And in 2005, the court ruled that Congress could prohibit someone from growing marijuana in her yard for her personal medical use, because federal laws against drugs are a kind of economic regulation.
Still, the court has never held that the federal government may compel people to participate in commerce. And this is what makes the individual mandate unprecedented: Never before has Congress presumed to order average Americans to purchase a good or a service in the marketplace.
Simply from the standpoint of semantics, the law's defenders face a challenge. As ordinarily understood, the word, "regulate," implies rules for activity that people have freely chosen to engage in (running a business, for instance). The word doesn't imply forcing people, say, to start a business in the first place.
Likewise, "commerce" implies economic activity - but someone who fails to …