Among the starkest contrasts between John McCain and Barack Obama is the dramatic difference in their promised approaches to judicial appointments, especially to the closely divided Supreme Court.

McCain, eager to establish credibility with conservatives, has bashed liberal "activist judges" who intrude into "policy questions that should be decided democratically,"and essentially vowed to move the Court sharply to the right in judicial philosophy.

The presumptive Republican nominee has identified Bush-appointed Chief Justice John Roberts and Justice Samuel Alito as models.

Obama, who voted against both men during their Senate confirmation hearings, has said that they and the Court too often side with "the powerful against the powerless" and lack "empathy" for ordinary people. The presumptive Democratic nominee exudes determination to move the Court sharply to the left if he gets the chance.

At a time when the Court is precariously balanced–with four conservatives, four liberals (including the two oldest justices), and the ideologically eclectic Anthony Kennedy–these contrasting approaches have provided opposing activists with nightmare visions to rally the Democratic and Republican bases during the presidential race.

Imagine that two years hence, Sen. Hillary Rodham Clinton, or Sen. Barack Obama, or former Sen. John Edwards is president. She or he will be trying to fill dozens (eventually) of vacancies on federal Courts of Appeals with liberal-leaning nominees. And perhaps one or two Supreme Court vacancies as well.

If and when those nominees face Republican filibusters or other tactics to deny them floor votes, what standing will the new Democratic president have to protest? How, for example, could Obama show his own nominees to be more deserving of confirmation than former Mississippi Judge Leslie Southwick, who is under attack by Obama and other Senate Democrats simply because liberal interest groups consider him too conservative?

Southwick, who is a professionally well-qualified and personally admirable Bush nominee for the U.S. Court of Appeals for the 5th Circuit (covering Louisiana, Mississippi, and Texas), is the latest victim of a judicial confirmation process that has steadily become more degraded by partisan warfare in recent decades.

Senate Democrats’ treatment of Southwick will show whether they are so shortsighted as to provide their Republican adversaries with new precedents and excuses for a campaign to obstruct the next Democratic president’s liberal nominees, no matter how well qualified.

If "too conservative" is reason enough for Democratic senators to block a floor vote on Southwick, who is no right-wing culture warrior, then "too liberal" will be reason enough for Senate Republicans to do the same when the shoe is on the other foot.

The long-term cost to the country is that bit by bit, almost imperceptibly, more and more of the people who would make the best judges — liberal and conservative alike — are less and less willing to put themselves through the ever-longer, ever-more-harrowing gantlet that the confirmation process has become.

A year after conservative Justice Samuel Alito succeeded liberal-leaning Justice Sandra Day O’Connor, a disagreement between two of the nation’s best legal journalists about how much President Bush has transformed the Supreme Court prompts this challenge to Court-watchers:

What will the legal landscape look like in 10 years? Make your predictions and place your bets.

In a widely acclaimed book full of revelations about behind-the-scenes battles over the Court, Jan Crawford Greenburg, now of ABC News, says that after decades of disappointment, conservatives have finally won the day. The appointments of Alito and Chief Justice John Roberts will produce a "profound and lasting alteration," Greenburg writes in Supreme Conflict: The Inside Story of the Struggle for Control of the United States Supreme Court. They and their allies will now engineer "one of the most fateful shifts in the country’s judicial landscape in a generation … with repercussions as yet unimagined," she predicts.

"I’m not holding my breath," retorts Benjamin Wittes in The New Republic Online. Wittes, an author and a guest scholar at the Brookings Institution who until recently wrote the nation’s smartest legal editorials for The Washington Post, highly recommends Greenburg’s book (as do I) for its "genuinely spectacular" reporting. But he dissents from her view that Bush has set the stage for an era of conservative hegemony.

To advance this intriguing discussion, I offer specific predictions below and invite others to offer theirs.