The cover for the ESA is of course the interstate commerce clause, which is the wedge by which the federal government has become the regulatory state never intended by the Founders. Roberts seems to want to limit the commerce clause to permit federal jurisdiction only when the activity itself is interstate. If only the toad would schlep itself even occasionally to Reno, Roberts would gladly enjoin anyone who would molest it. Unfortunately, Roberts points out drolly, the ``hapless toad ... for reasons of its own, lives its entire life in California.''

     This is a thin reed on which to hang a constitutional philosophy. But it's about all we got. Does this portend a justice who will demolish the underpinnings of the regulatory state and seven decades of commerce clause precedent?

     Who knows. But I doubt it. Remember, in the most recent commerce clause review, the California marijuana case, even Antonin Scalia, no enemy of the wrecking ball, refused to follow Clarence Thomas in using the case to undermine the very expansive modern interpretation of the commerce clause.

     And Roberts is no Scalia. I think. Like just about everything else we can say about him, this guess is educated only by the meager record, and by Roberts' traditional, conventional life trajectory. And perhaps even by his opening remarks on national television, where he spoke with reverence of the institution to which he has been nominated -- from which one might infer (now we're really grasping at straws) -- that he might be reluctant to overturn precedent.

     But if he is no Scalia, is he an O'Connor -- who moved so steadily leftward through her Washington career that she has become a retroactive icon, a paragon of principled conservatism, to liberal advocacy groups today?

     We know that Scalia and Thomas would overturn Roe v. Wade tomorrow. As would Rehnquist, for whom Roberts clerked and to whom he is being most closely compared.

     O'Connor, on the other hand, not only upheld the abortion precedent, but invented an even more radical constitutional principle to justify her decision. The notorious pronouncement that ``at the heart of liberty is the right to define one's own concept of existence, of meaning, of the universe, and of the mystery of human life'' opened the door to the Texas case ruling anti-sodomy laws unconstitutional, and Massachusetts' legalization of gay marriage on constitutional grounds.

     It is almost impossible to imagine Roberts doing something as grand as that. He would not have the audacity. My guess? He upholds Roe, purely for reasons of precedent. And very quietly.