The nomination of Elena Kagan to replace Supreme Court Justice John Paul Stevens, the legal lion of liberals for a generation, is the latest retreat by Democrats that reveals how conservatives in Washington differ from liberals, and why liberalism remains in retreat no matter how many elections Democrats win.

When President George W. Bush nominated Harriet Miers to the court, the conservative movement revolted. Bush withdrew Miers and named conservative Justice Samuel Alito. Senate Democrats refused to filibuster. Alito was confirmed. The court moved further to the right.

Now Senate Republicans don't even need to filibuster. Democrats fear a filibuster and retreat based on the threat, not the fact, fearing the fight.

Stevens is a legal and intellectual heavyweight of the first order. He is a brilliant legal tactician capable of crafting opinions that can win the support of a majority of justices. He is a master of the practices and procedures of the Supreme Court.

In the movies, Marlene Dietrich was the "woman of mystery." In the law, the woman of mystery is Elena Kagan, whose views on virtually every major legal issue are unknown. Her limited scholarship raises serious questions about whether she would support the expansions of executive power championed by President George W. Bush and whether she believes massive corporate spending by companies, which have vast amounts of money, can legally drown out voices of citizens, who don't.

I neither support nor oppose the Kagan nomination. I await her views being expressed in confirmation hearings, though the confirmation of Chief Justice John Roberts does not enhance faith in the confirmation process.

Roberts pledged to seek consensus on the court and to give great respect to legal precedent. As chief justice, he has done the opposite, throwing out long-held precedents, moving the court to the right, bitterly dividing the court in the process.

The Clinton Library should release all papers illuminating Kagan's role during the Clinton presidency. Limited evidence suggests a tendency to advise repeated tactical retreats on key issues, and to write condescending notes on memos of those advising contrary views. Hopefully the Clinton papers will rebut this perception. What if they don't?

There is widespread misunderstanding about the means of persuading Justice Anthony Kennedy to vote a certain way. Kennedy is not a shallow man who can be charmed at dinner, romanced by smooth talk or impressed by elitist credentials. He must be persuaded by the arguments of the law, based on the substance of the law, not the personality of the lawyer.

Stevens is so influential because of his legal brilliance in crafting opinions that can attract a majority of justices. He is not a campaigning politician or world-class schmoozer. He is one of the legal giants of our generation.

There is no evidence, pro or con, whether Elena Kagan possesses these qualities. She has no record of judicial leadership, brilliant legal advocacy or high-impact legal scholarship.

My hope is that Kagan rises to the occasion during her confirmation. My worry is that she moves the court even further to the right. My advice is that senators listen carefully before voting to fill the indescribably important seat of Justice John Paul Stevens.