An entirely reasonable decision

There were two main arguments for the constitutionality of the healthcare law: The Commerce Clause of the Constitution, and the constitutional right of the Congress to levy taxes. Both of these clauses are part of Article 1, section 8 of the Constitution, which enumerates the powers of Congress. Most of the discussion preceding the decision was  about regulation of commerce, which seemed to me and, I think, many others, to be not such a good idea -- both as a practical argument, given the nature of the Supreme Court, and even, perhaps, as an unhealthy extension of the powers of Congress.

The Obama administration was excoriated by many for not making the "individual mandate" an explicit tax, thus side-stepping a questionable resort to the Commerce Clause; it turns out that they were clever enough to phrase the penalty part of the mandate in terms of a tax collected on people who chose not to buy insurance. Give them credit; they had even argued precisely that point in 2010, as did, I heard, Justice Sotomayor recently.

Of course, 4 conservatives (this time Justice Kennedy as well as the usual 3) didn't buy the argument. Justices Scalia and Alito are too firmly committed to right-wing ideology to be open to any such argument; Thomas, of course, goes with Scalia. Justice Roberts, on the other hand, quoting a beautiful phrase from a previous case (Hooper v California) wrote in the majority opinion:

Because "every reasonable construction must be resorted to, in order to save a statute from unconstitutionality," Hooper v. California, 155 U. S. 648, the question is whether it is "fairly possible" to interpret the mandate as imposing such a tax..."

I really like the idea that the highest court must assume, by default, that a statute is constitutional, and should always be on the lookout for a way to recognize it as such. If that is truly Roberts position, there is hope that he may turn out to be, on balance, an excellent Chief Justice. Now if only he would change his mind on Citizens United...