Empirical Evidence for the Phantom Menace?

Judge Posner in the Post today:

We must do better. The terrorist menace, far from receding, grows every day. This is not only because al Qaeda likes to space its attacks, often by many years, but also because weapons of mass destruction are becoming ever more accessible to terrorist groups and individuals.

My first, minor point is that if it is true that "[t[he terrorist menace . . . grows every day," then the War on Terror has been the worst-fought conflict in the history of superpowers. If the war started on September 11, 2001, then we are four years in and, according to the good judge, we are not just losing, but getting farther behind every single day. I mean, I've heard a lot of talk about defeatism lately, but doesn't this take the cake?

But my second, more important point, is that there's simply no empirical evidence for this claim, at least not that ordinary mortals (and Article III judges) have access to. "The terrorist menace . . . grows every day." Every day? It never goes down, like when we capture an al Qaida number three? Or find a laptop with information?

Even worse, what is the terrorist menace? Is this the risk of an attack, in terms of a probability? If so, then how does one estimate that probability?

Is it true that "weapons of mass destruction are becoming ever more accessible to terrorist groups"? If so, then the president and his people must be doing an awful job, in the judge's opinion.

Link.

The problem is that language like this is the enemy of rational thought. On September 11, 2001, the United States was attacked by a distinct group of people, al Qaida. That group has a leadership structure, rank-and-file personnel, recruitment processes, and finances, just like any other group. It can be attacked at any of those points in its structures, and we have attacked it. Repeatedly.

But if we think that September 11 demonstrated the terrorist menace, some kind of ill-defined threat that is everywhere, all the time, and always growing, growing, and spreading, infiltrating . . . then we can't fight that kind of Phantom Menace, let alone hope to prevail against it.