Krugman is talking about how the people who have succeeded in the administration are those who are more interested in politics than those interested in providing the real answers about the economy.
In what Keynes considered to be Hayek's "grand book", Hayek talks about why the worst end up on top. I just reread some of that section, and of course it talks more about totalitarianism and socialism specifically than the market democracy of the United States and the Obama administration. But the point is the same: politicians succeed in politics. Often, economic science suffers or simply fails to make a dent.
This post makes largely the same point about the new prominence of anti-Keynesianism among Democrats.