Robert Farley points out that no one "remembers disasters that don’t occur, or recalls waves of refugees that never show up":
Success and failure in crisis response, consequently, have asymmetric political effect. The Obama administration’s response to the Haiti earthquake, in my view, has been a resounding success for responsible, capable governance. No one will remember that in six months.
Bush’s response to Katrina will endure in the political memory for decades. On the one hand this is (politically) good for progressives, given that conservative efforts to gut governance tend to result in horrible disasters. On the other hand, because policy and execution failures stick in the mind longer than successes, it’s difficult to convince the general public of the importance of a responsible approach to government. In the rhetoric of anti-statist nutjobs, Katrina actually becomes an argument against adequate government, while success in Haiti fades from history.
Yglesias applies this dictum to the administration's economic policy. It can also be said to apply to successful anti-terror policy. The more it succeeds, the less useful it appears.