Robert Levy disputes the pro-ACA interpretation:
The Commerce Power is expansive. But [the Patient Protection and Affordable Care Act or PPACA or ACA]'s mandate stretches beyond dictating how a product may be produced, distributed, exchanged, or consumed. The mandate actually compels that a transaction occur – the purchase of health insurance, which cannot legally be acquired across state lines. Neither an act nor an interstate market exists to be regulated. Essentially, the PPACA mandate is regulatory bootstrapping. Congress forces someone to engage in commerce so it can regulate the activity under the Commerce Clause.
Tackling the notion that the healthcare market is in some way exceptional, Ilya Somin worries about the precedent the ACA sets for congressional power:
In the Sixth Circuit case, Judge Sutton and Judge Boyce Martin resolved the issue by simply ruling that the Commerce Clause gives Congress the power to regulate inactivity on the same basis as "activity." This approach pretty obviously leads to unlimited congressional power to impose mandates. Under current precedent, Congress can regulate any that it has a rational basis for believing that it affects interstate commerce, in the aggregate.
That, of course, is true of virtually any activity of any kind. It is also true of virtually any failure to engage in activities, especially economic transactions. Any failure to purchase a product has some substantial economic effect, at least when combined with similar failures by other people. This is true of failures to purchase broccoli, failures to purchase cars, and so on. …
If the Court upholds the individual mandate, it will not be able to do so in a logically consistent manner without opening the door to virtually any other mandate. As UCLA law professor Adam Winkler points out in his contribution to this symposium, the government's numerous briefs in the various mandate cases all fail to explain how there can be any for Justices who might be inclined to uphold this law, but also want to maintain limits on congressional authority. The dilemma is exacerbated by the fact that this "slippery slope" problem is not merely theoretical.
The Dish 