The resignation of Karl Rove ends the tenure of a man who has occupied a unique place in American history. No other presidential appointee has ever had such a strong influence on politics and policy, and none is likely to do so again anytime soon. Only Robert Kennedy exerted similar influence, and he had little to do with electoral politics during his brother's presidency.
Rove brought to his work a wide and deep knowledge of U.S. history, political statistics, demography and public policy. He worked hard and, for most of three years, under an unjustified threat of indictment. He does not seem to have weighed in much on foreign or military policy, and there is no reason to believe that George W. Bush sought his advice on whether to take military action in Iraq. But otherwise, he seems to have had his hand in everything from the details of the Medicare prescription drug bill to who should be the Republican nominee for the Senate in Minnesota. His effectiveness was grounded in the belief -- accurate, it seems, to the end -- that he had the full confidence of the president.
What is the verdict on his legacy? Rove is, as Bush put it, the "architect" of his political and policy strategy, and to many, that intertwined strategy seems to be in ruins. I take a longer view. For most of his career, Rove was a political consultant. In my own briefer career as a political consultant, I advised candidates running for executive office that they needed to come up with a small number of issue positions that would enable them to: a) get their party's nomination, b) win the general election and c) govern effectively.
I was surprised how few managed to carry this out. Bill Clinton, who drew on many consultants, did this quite well in 1992. Bush, with Rove at his side, did a pretty good job in 2000.
It's not easy. Going to the right (or left) can help in the primary but may hurt in the general. Policies widely appealing during the campaign may prove impossible to deliver on in government. Veering from your platform can be politically damaging, as Clinton discovered in 1994. But failing to adjust to changed circumstances can be a problem, as well.