George Will analyzes constitutional implications of the health care bills under consideration in Congress.
He makes some plausible arguments about provisions of those bills being unconstitutional. But there doesn't seem to be any obvious cut-and-dried case for unconstitutionality.
If the legislation is enacted, and a challenge comes to the Supreme Court, it will, as a practical matter, probably come down to whether 1) the "swing justice", Anthony Kennedy, goes along with the challenge; or 2) President Obama is able to replace any members of the Court's "conservative wing".
But, surprises do happen. If a good case can be made against any or all of a new health care structure, some from the "liberal wing" might be compelled to call it unconstitutional.
The Democrats would do well to consider what chaos would ensue, if they implement a plan, only to have it disallowed by the Supreme Court a couple of years or so down the line.