The Supreme Court rightly sees itself as the people's guardian against the legislature making unconstitutional laws. Thus, in the open hearing on Capitol Hill that was followed intently by millions of Americans, Scalia asked Verrilli of the individual mandate: "What is left? If the government can do this, what can it not do?" Alito later asked: "Could you express your limiting principle as succinctly as you possibly can?" Verrilli floundered over this line of questioning, and also came up sharply against the lawyers opposing Obamacare who invoked the Federalist Papers and the expressed beliefs on limited government of the framers of the Constitution. Even the ultra-liberal New Yorker magazine admitted: "It's well known that Verrilli had an off-day." For a British solicitor-general in similar circumstances it might have been possible airily to have belittled the 200-year-old views of a bunch of Virginian slaveowners — but not in America. 

So Obama himself had to step in, telling a news conference almost as soon as the hearings were over that he was "confident that the Supreme Court will not take what would be an unprecedented, extraordinary step of overturning a law that was passed   by a strong majority of a democratically-elected Congress". In fact the step would be far from unprecedented, as the former president of the Harvard Law Review must know, for in the two centuries since the doctrine of judicial review was established by the landmark 1803 case of Marbury v. Madison, the Supreme Court has struck down all or part of scores of laws passed by both Congress and the states. Furthermore, far from enjoying "a strong majority", Obamacare passed by 219 votes to 212 in the House and the bare minimum number of votes — 60 — to prevent a filibuster in the Senate. 

The bluster of Obama's press conference last month was designed to pressurise the five conservative judges on the bench, but also to frame a People v. Court angle for the coming election if they do indeed strike down Obamacare. Will it succeed? One thing that was almost unprecedented was for the President to comment at all on a decision before it had been made. Even Thomas Jefferson's fulminations against the Marshall court and Franklin Roosevelt's against the Hughes court took place behind the scenes before the decision was taken and in public afterwards, rather than publicly beforehand. 

Although Obama's intervention is unlikely to raise so much as an eyebrow of Justices John Roberts, Clarence Thomas or Anthony Kennedy, let alone Alito or Scalia, it has raised an issue the President might not have wanted placed so prominently in the election campaign. For as Mitt Romney told a rally of the National Rifle Association on April 13: "In his first term we've seen the President try to browbeat the Supreme Court. In his second term, he would remake it." No fewer than four justices are in their seventies — Scalia is 76, for example — and so it is likely that a re-elected Obama would be able to reverse the 5 to 4 conservative majority on the bench, with profound implications for American politics, possibly lasting for many years after he left the White House.