The appeal of "intelligent design" to the American right is obvious. For religious conservatives, the theory promises to uncover God's fingerprints on the building blocks of life. For conservative intellectuals in general, it offers hope that Darwinism will yet join Marxism and Freudianism in the dustbin of pseudoscience. And for politicians like George W. Bush, there's little to be lost in expressing a skepticism about evolution that's shared by millions. In the long run, though, intelligent design will probably prove a political boon to liberals, and a poisoned chalice for conservatives. Like the evolution wars in the early part of...