Last week, coincidence brought together a pair of worthy articles attacking the political adage that terrorism is an “existential” threat.

Gene Healy debunked “existential” in his Examiner column. “Conservatives understand that exaggerated fears of environmental threats make government grow and liberty shrink,” he writes. “They’d do well to recognize that the same dynamic applies to homeland security.”

John Mueller and Mark Stewart, meanwhile, have an article on Foreign Affairs’ web site titled: “Hardly Existential: Thinking Rationally About Terrorism.” They show that conventional assessment methods place terrorism so low on the scale of risks that additional spending to further reduce its likelihood or consequences is probably not justified.

But some readers literally can’t absorb what appears in the two paragraphs above. You might be one of them.

Exquisitely rational arguments like these are “cognitively invisible” in the face of fear, as Priscilla Lewis puts it in the forthcoming Cato book Terrorizing Ourselves. I assume the arguments of Healy, Mueller, and Stewart will be dismissed out of hand by people who view terrorism through their personal lens of fear.

Mueller and Stewart touch on this problem briefly:

Because they are so blatantly intentional, deaths resulting from terrorism do, of course, arouse special emotions. And they often have wide political ramifications, as citizens demand that politicians “do something.” Many people therefore consider them more significant and more painful to endure than deaths by other causes. But quite a few dangers, particularly ones concerning pollution and nuclear power plants, also stir considerable political and emotional feelings, and these have been taken into account by regulators when devising their assessments of risk acceptability.

We know enough to be confident of our security. The questions remaining include: How do we convince others to join the ranks of the indomitable Americans? How do we undercut the political advantage taken of terror fears? And how do we rein in the massive government growth produced by terror politics?