Conservatives concede that the Democrat-led Senate would almost certainly confirm any Obama nominee, absent any damaging revelation. But the more liberal the nominee, the more contentious the confirmation hearings will be. The president's stance as a consensus builder might suffer if his first choice seems likely to support liberal causes such as gay marriage.

Conservative critics sense a preference for liberal "judicial activism" in Obama's claim that "the truly difficult" legal cases "can only be determined on the basis of one's deepest values, one's core concerns, one's broader perspectives on how the world works, and the depth and breadth of one's empathy." He voted against Chief Justice John Roberts and Justice Samuel Alito, complaining that the two Bush appointees had sided with "the powerful against the powerless." When it's Obama's turn to pick a nominee, he'll either sacrifice some political good will or he'll upset his base. There's not much middle ground.

Obama will have a choice: He can give the Left what it wants and weaken our defenses. Or he can follow the advice of his more prudent advisers, recognize that Congress, the courts, and officials including Attorney General Michael Mukasey have already moved to end the worst Bush administration abuses -- and kick the hard Left gently in the teeth. I'm betting that Obama is smart and tough enough to do the latter.