I haven't had a whole lot of chance to study President Obama's nominee to the Supreme Court, Elena Kagan, but I do know a little and had a couple of thoughts about it.
A lot of liberals have expressed concern that Kagan is a "moderate," and not an open liberal; this is a problem in their eyes because she's replacing John Paul Stevens, who is a liberal.
I'd point out a few things. When I was getting my Bachelor's and Master's degrees in Political Science in the early and mid-eighties, one of the things I learned was that there's a long history of Supreme Court justices turning out to be something completely different from what the person nominating them thought they'd be. Justice Stevens, was a prime example of this. He was a lifelong Republican when Gerald Ford nominated him to the court. Now he's considered the bulwark of liberalism on the Court. Earl Warren, who was the Chief Justice during the time of the court's "Brown vs. Board of Education" decision that ruled against school segregation, was a Republican who as Attorney General of California (he was also Governor later) was the driving force behind the internment of Japanese-Americans during World War II. Brown vs. Board of Education was one of many "liberal" rulings his court had. Hugo Black was, when he was younger, a member of the Ku Klux Klan, and as a Senator tried to filibuster Civil Rights laws. As a justice, his record supporting civil rights was excellent. I came across a great quote about Black from the late Carl Sagan: "as a young man, he dressed up in white robes and scared black folks; when he got older, he dressed up in black robes and scared white folks."
My point is that trying to predict the future rulings of a person once they get onto the Supreme Court is pretty much a fool's errand. The Republican party found this out the hard way in nominating David Souter; he was expected to help in overturning Roe vs. Wade, the ruling that essentially legalized abortion across the United States. However, when a serious legal challenge was mounted to it in the early nineties, Souter, to the surprise of the people who consider themselves "conservatives," acted as a conservative in the Edmund Burke model of conservatism; he voted against overturning Roe vs. Wade, explaining that there has to be a compelling reason to overturn a long-standing legal principal. Since the Roe vs. Wade precedent had been working, in his legal and intellectual opinion, quite well for about two decades, there was no reason to abandon it.
Various objections to Ms. Kagan's nomination have arisen and been batted down. She's never worked as a judge. Many people who went on to be fine Supreme Court justices were never judges, including Thurgood Marshall who, like Ms. Kagan, was Solicitor General (and had, in fact, been the NAACP lawyer who argued Brown's side in Brown vs. Board of Education).
All of that said, I think I know why President Obama has chosen Ms. Kagan. One of the criticisms of her is that as Dean of Harvard University, she was a pit bull. I would argue that this is exactly why she's been chosen. In a court that's presided over by the mediocrity that is John Roberts (who himself served very little time as a judge), the right-wing pit bull is Anthony Scalia. I'm confident that Ms. Kagan will rule in a manner that makes me happy. What I'm happier about it that she will serve as a counterweight to Scalia, pushing the fence-sitting justices into decisions that, if not liberal, will be judged on their legal merit rather than Scalia's poliitcal agenda. This is going to be important. The next nomination will be for Ruth Bader Ginsberg's slot; she's got pancreatic cancer, a terminal illness. Like Stevens, we'll be replacing a liberal with a liberal. Roberts is young-- 55. We'll be stuck with him, as well as Sam Alito, (60 years old and someone who never served a day as a judge) for a long time. If we're going to not spend the next 20 years having horrendous decisions from the Supreme Court (such as the recent decision that ruled that corporations have the right to give unrestricted amounts of money to political campaigns, as if they were individuals), we're going to need a pugnacious jurist. I have a feeling that Ms. Kagan will fill the bill.
When Sonia Sotomayor was nominated, I pointed out that I hope to see a Supreme Court that looked more like the United States in my lifetime, and that it was a step in that direction. There are rumors confirming and denying whether or not Ms. Kagan is a lesbian. I could care less about her sexuality as far as her merits as a justice. But there's a part of me that hopes it's true, and that she is, as is expected, confirmed, because not only will the Supreme Court look a little more like America: it'll be fun watching Antonin Scalia's head explode when he realizes that he's lost a legal argument to a dyke.