Rumors were going around about Justice O'Connor retiring, but it was still a shock to see the screaming headline. Man, oh, man. We all knew Rehnquist was on the verge of retirement. But the fight over Rehnquist's spot was never really a big deal, because the fundamental complexion of the court wouldn't have changed. The Chief Justice is easily the worst justice on the Court, a right-wing, results-oriented hack with a particularly atrocious view of defendants' rights. He's a conservative judicial activist, and his replacement, whomever he or she is, can't be much worse.
O'Connor's retirement is a completely different matter. She is *the* critical swing vote on a myriad of cases ranging from states' rights to 1st Amendment issues to abortion. O'Connor's not really a "moderate," but political labels could never completely describe federal judges, who are guided by judicial philosophy and other concerns. But her judicial philosophy, which is fundamentally pragmatic, moderated her conservative politics. In law school, some of the more intellectually rigorous types (there were a few who actually cared about judicial philosophy) would dog on O'Connor for her unprincipled, ad hoc opinions. True, she belonged to no well-defined school of jurisprudence, but in this Court, that's preferable to the hypocrisy of would-be originalist Antonin Scalia. O'Connor's always grappling with the facts of a case. Her chief legacy will probably remain Planned Parenthood v. Casey, the case that reaffirmed and refined Roe v. Wade, where she carved out areas various boundaries for state infringement of a fundamental right under an "undue burden" test. Parental notification and 24-hour waiting period laws are okay under this rule.
Personally, I find the entire line of "right to privacy" cases to be rather sloppily argued, including Roe and Casey. But the court isn't academia, and when you need to carve out a compromise solution with real life consequences, you can count on O'Connor to draft an opinion with a narrow scope. So even though she has a legislator's temperament for Frankenstein law, O'Connor tries to limit the reach of Supreme Court decisions, which, on balance, is a good thing, regardless of what the composition of the court is. Judicial restraint is usually a good thing.
O'Connor's routinely described as the most powerful woman in America. That's probably right. She's the most powerful figure in the Court simply because she's the justice that both sides often end up vying for. Stories abound about how justicies try to craft first drafts of opinions specifically tailored to Sandra Day's taste to try to win her over. Her late-breaking swing into the majority in Casey essentially saved Roe v. Wade. But should Roe v. Wade be saved at all costs? That seems to be the standard progressive position. A pro-Roe justice has just retired, as some may take nothing less than O'Connor II.
That's a bad idea. Dubya owes his base, big time, and if he wants to wait until Rehnquist goes to nominate a wingnut activist, he's still not going to use this slot to nominate anyone who may potentially become David Souter II. I'd be happy with Alberto Gonzales, the current Attorney General. Or guys like Luttig or McDonnell, who at least sound like principled conservatives. Why have a one-issue litmus test when the Supreme Court rules on so many matters of great importance? And on non-abortion issues, Justice Kennedy has become a swing vote himself, so not all is lost.
Someone made the argument that the progressives have lost their political instincts because they don't ever try to make their case to the public anymore. Instead, they go to courts. I agree. Abortion should've always been a congressional matter, and had it remained there, I expect that progressives would have been kept on their toes, organizing and mobilizing to insure the right to choose, rather than sit back and let the one swing justice decide the matter. O'Connor wasn't an abortion rights true believer. Court watchers think she reaffirmed Roe because she was loath to overrule precedent, especially one of defining as Roe. Abortion rights advocates won't be so lucky next time.
 Two recently handed-down opinions, both controversial, show the inadequacy of political labels. The moderate-liberal bloc struck down a state's legalization of medicinal marijuana due to their expansive reading of the commerce clause (which gives Congress broad powers to regulate commercial activities). Then that moderate-liberal bloc (give or take one or two justices) then expanded the government's eminent domain powers, to the consternation of many liberals on the lefty blogs I frequent. "Liberal" and "conservative" really don't fit the reasoning behind those decisions. Bush will nominate a "conservative", but it's possible his nominee will be governed by something other than just wingnuttery. I'd settle for a principled state's rights guy. Someone who won't betrays his principles for political expedience a la Bush v. Gore.