Hendrik Hertzberg's "Talk of the Town" piece on Harriet Miers is well worth reading in full. It concludes:

Sinking Miers's nomination would give Democrats the satisfaction of dealing Bush a defeat while at the same time striking a blow against the intellectual degradation of the Court. But Bush's next nominee would almost certainly be both more distinguished and more provably, fearsomely right wing. To fracture the formula of a founding father of modern conservatism, mediocrity in the defense of moderation isn't much of a vice. And excellence in the pursuit of extremism is certainly no virtue.

However the Miers nomination turns out, the fact that Bush submitted it is an unflattering reflection on his character. In the Federalist No. 76, Alexander Hamilton writes that the Senate's role in confirming appointments is designed to make the President

both ashamed and afraid to bring forward, for the most distinguished or lucrative stations, candidates who had no other merit than that of coming from the same State to which he particularly belonged, or of being in some way or other personally allied to him, or of possessing the necessary insignificance and pliancy to render them the obsequious instruments of his pleasure.

Hamilton was no naïf about human nature, but in the present case his formula seems to have underestimated the Presidential capacity for both shamelessness and—well, courage isn't quite the right word. Arrogance.  [full article]