That is a question that surely deserves consideration, doesn’t it? In the Washington Post, two attorneys, David B. Rivkin Jr. and Lee A. Casey, cite a number of Supreme Court precedents that would indicate that a law mandating that everyone purchase insurance would not pass constitutional muster. According to the rulings and the case law they cite, Congress has no authority under the much-invoked commerce clause to require private economic transactions. Nor can Congress use its taxing power–as has been proposed, to impose tax penalties on those who do not buy health insurance–as a way of regulating what it is not allowed to regulate under the commerce clause.
Though these attorneys have served in Republican administrations, they don’t seem to be raising a mere conservative objection. In fact, they say that the single-payer option probably WOULD be constitutional. They are simply pointing out constitutional and legal problems with the current insurance-based proposal.