When it comes to the core of the court's work, determining the contemporary meaning of the Constitution, it is ideology, not craft or skill, that controls the outcome of cases. As Richard A. Posner, the great conservative judge and law professor has written, "it is rarely possible to say with a straight face of a Supreme Court constitutional decision that it was decided correctly or incorrectly." Constitutional cases, Posner wrote, "can be decided only on the basis of a political judgment, and a political judgment cannot be called right or wrong by reference to legal norms." 

When it comes to the incendiary political issues that end up in the Supreme Court, what matters is not the quality of the arguments but the identity of the justices. There is, for example, no meaningful difference between Scalia and Ruth Bader Ginsburg in intelligence, competence, or ethics. What separates them is judicial philosophy -- ideology -- and that means everything on the Supreme Court. Future justices will all likely be similarly qualified to meet the basic requirements of the job. It is their ideology that will shape the court and thus the nation. 

So one factor -- and only one factor -- will determine the future of the Supreme Court: the outcome of presidential elections. Presidents pick justices to extend their legacies; by this standard, George W. Bush chose wisely.

McCain has already emphasized that he will select judges modeled after the two men elevated to the High Court by President Bush, and he is shrewd to do so. No issue matters more to conservative Christians than the composition of the court, which often adjudicates the issues they care about most, from sexual behavior to religious expression. 

Liberals care about the same issues, but they have a long list of additional concerns that could come before the court in the years ahead, from the rights of workers and prisoners to the rules on wiretapping. 

The two Bush appointees have tilted the court to the right . . .  Change is clearly coming (Justice John Paul Stevens is 88), and the new president could reshape the court for a generation.

The upward and downward blips that Americans have experienced in the past quarter century, despite their considerable impact on the profits of big corporations and the lives of real working people, don't amount to all that much when measured on a scale that spans centuries, however. Not for nothing have the past few decades been dubbed by economists as the "Great Moderation." The rich have gotten richer, the poor poorer, and the middle class relentlessly squeezed, but there have been no society-wide economic dislocations in recent years that match the inflation-and-unemployment miseries of the late 1970s, much less the outright disaster of the Great Depression.  

Until now? Consider the following extraordinary commentary: Alan Greenspan saying, "The current financial crisis in the US is likely to be judged in retrospect as the most wrenching since the end of the second world war." Former Reagan economic advisor Martin Feldstein saying, "Could this become the worst recession we have seen in the postwar period? I think the answer is yes." Paul Krugman writing that the current situation "looks increasingly like one of history's great financial crises."

The New Deal didn't emerge of its own accord as some kind of organic reaction to the Great Depression. Leadership was required, and the political fights were brutal. The same will no doubt be true for any sustained effort to crack down on Wall Street shenanigans and redistribute wealth more equitably. Indeed, for most of the past 25 years just imagining such a thing would have seemed ludicrously out of touch with political reality. But that's what makes the current events so dramatic. The dangers -- of great economic distress and turmoil -- are clear and intimidating. But the opportunity for reform is fantastic.