SECONDS AFTER President Bush announces his choice to replace Supreme Court Justice Sandra Day O'Connor -- whenever that happens and whoever the nominee is -- liberal interest groups will release a blast of e-mails promising a "rollback" of American liberties if the person is confirmed. Conservative groups, at the same moment, will blitz with e-mails proclaiming the nominee a modern John Marshall. Ads will appear on television. Journalists will be hit with distorted "reports" attacking or defending the nominee's "record," as groups release their opposition research or their defensive spin. Both camps, in short, will unleash the huge sums they have raised in what will be, for all intents and purposes, a political campaign -- a political campaign, unfortunately, for an office that is meant to be not merely apolitical but actively insulated from politics.

The campaign, in reality, began long ago. It began when both sides made the judgment that they had to invest in judicial appointments -- particularly Supreme Court appointments -- to make sure they got the results they wanted from the courts. At this point, the war has become a Washington industry, fed by both sides' wounds from the past, real and imagined, and fears for the future, realistic and fantastical. Barely had Justice O'Connor announced her retirement Friday when the liberal People for the American Way was promising to "help lead the fight against any terrible changes to the Supreme Court." The conservative Family Research Council vowed that the "public is primed for the fight it will take to confirm a nominee" and promised "significant grassroots support for the President's nominees." A lot of people on both sides actively want a fight.

The war is about money and fundraising as much as it is about jurisprudence and the judicial function. It elevates partisanship and political rhetoric over any serious discussion of law. In the long run, the war over the courts -- which teaches both judges and the public at large to view the courts simply as political institutions -- threatens judicial independence and the integrity of American justice.

So we take this moment, when nobody knows how excellent or terrible the next nominee will be, to emphasize that a judicial nomination is not a political campaign and should not be treated as one. A nominee's record is almost never a simple affair, because good legal reasoning doesn't always render the most politically congenial answer. Demagogic attacks on almost any nominee are easy, and knee-jerk defenses equally so. But a reasonable assessment of the president's choice, whoever it is, will not emerge from such a shouting match.

We say this not in hopes that the war rooms will shut down and the campaign atmosphere give way to a serious discussion of -- and with -- the eventual nominee. That won't happen. But somehow, the serious discussion needs to take place even in an atmosphere that so disfavors it. The only legitimate source of the power of the Supreme Court -- which is, after all, a group of unelected officials who serve for life -- is the premise that interpreting law is not the same as creating it, that the task of judging, in other words, is not a political function. The war rooms, the money and the rhetoric all speak to a loss of faith in that premise on the part of groups who are now fighting over political spoils. Those Americans who still believe in the Third Branch need to endeavor to tune those special interests out.