Before the president proposes a Supreme Court candidate to replace Sandra Day O'Connor, he might want to recall key lessons of her 24 years on the bench.
Merely by being the first woman on the court, she furthered the idea that a greater diversity of backgrounds among judges can help improve the task of interpreting the law. Her success, both as a discerning justice and symbol of equality, inspired many women to become lawyers and reach for the top levels of government.
While Justice O'Connor brought the sensibilities of her Western ranch and legislative lives to her work - resulting in rulings that were largely moderate conservative - she was ever mindful of the need for courts to decide tough issues case by case, and not with sweeping new interpretations. The court's integrity rests on both honoring precedents and not pushing for strong moves to the left or right. As a result of such middle-of-the-road balance, her vote in an often-divided court made her the most powerful woman in US domestic affairs.
By being a moderate, she trimmed off the excesses of the court's most controversial decision, Roe v. Wade, redefining "right to privacy" (which isn't in the Constitution) as "liberty," and laid down better rules on when abortion is legal.
Her "bright line" in many of her decisions was to weigh the potential impact of rulings on real people. She judged each case narrowly on the facts but broadly against the Constitution. That can often create much uncertainty, leaving citizens at loose ends about whether society is always governed by the same guiding principles. But it can also be reassuring that some justices are concerned about the real-world effects of their choices.
Mr. Bush, too, should be equally mindful of his coming historic choice.