Today's argument was one hour and 29 minutes long. Tomorrow, the court has allotted two hours for the main event -- the argument over the individual mandate.

The ACA requires that virtually every living person in America -- except for illegal aliens and some other, incredibly narrow, categories -- must buy health insurance.  For the first time in the history of this nation, the federal government is requiring Americans to engage in commerce merely because they are alive.

There are a lot of requirements that arise once a person decides to participate in commerce, but there has never before been a law forcing people to make economic decisions.

The argument over the individual mandate --- also known as the mandatory coverage issue -- will focus on whether the federal government has the power to impose the mandate based on the Commerce Clause or the Necessary and Proper Clause.  

Article I, Section 8 of the Constitution provides:

The Congress shall have Power - To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof.

This provision only permits the Congress to make laws that are necessary to carry out its other powers, so to find the mandate "necessary and proper," the court will have to decide whether the mandate is permitted under Congress's other powers, which sends us right back to the Commerce Clause, Article I, Section 8:

The Congress shall have Power [...] To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;

Commerce doesn't exist to be regulated until people engage in commerce.  The ACA forces people to engage in commerce, then regulates them.  There has never been a law like it, and the only reason there is any argument about its constitutionality is the Supreme Court's historical and ridiculous distortion of the Commerce Clause in the support of political aims.

The modern, nearly limitless, interpretation of the Commerce Clause had its genesis in the 1942 case of Wickard v Filburn.  The U.S. government had established a Depression-era scheme designed to prop up the price of wheat, and it worked.  In 1941, wheat producers cooperating with the "Agricultural Adjustment" program received $1.16 a bushel, compared to the world market price of $.40 a bushel.  

The federal regulations established wheat production limts based on acreage.  Filburn was a farmer who decided to grow more than his allotment, but he grew the wheat for his own use; he did not sell any of the wheat in interstate commerce.   Nonetheless, the court found that Filburn had violated the law, which was a valid exercise of government power under the Commerce Clause.  The court reasoned that, if Filburn had not grown the excess wheat for his own use, he would have had to buy wheat on the open market.  Although Filburn alone might not have been able to affect the market, the cumulative effect of thousands like him would be substantial.  Therefore, Congress has the authority to regulate a completely intrastate market if the cumulative effect of such activities would have a substantial effect on interstate commerce.

Thus, constitutional doctrine was founded on the "what-if-everyone-did-that" argument, explaining at least in part why Wickard v Filburn makes most lists of the worst Supreme Court decisions in history.

The health care cases go beyond Wickard.  Way beyond Wickard.  If the ACA is upheld as a constitutional exercise of Commerce Clause authority, there is nothing the federal government can't require under the same theory.  The government can tell us what to eat, what to wear, what to do, how many children to have -- there will be no limit.

To put it in Wickard terms, upholding the ACA would mean the government could not only tell us not to produce excess wheat, it could force us to stop producing wheat altogether and buy that wheat only from government-sponsored exchanges.  That is, it could if the anti-gluten forces didn't get there first.

In other words, this case is huge.  The hugest.  Stay tuned.