Devilishly clever monster that he is, the "beltway sniper" and his accomplice seem to have timed their actions perfectly to first mislead foolish bloggers such as myself into pegging him as a possible terrorist, then humiliate us by shifting his behavior to fit the profile of a typical none-too-bright, rather disorganized lone nutbar. (Oddly enough, some bloggers, including Instapundit Glenn Reynolds, are still seeing hints of terrorism in the latest developments. We can only hope, I suppose, that all terrorist organizations are clueless enough to leave incoherent notes for the authorities, telephone them repeatedly with hints about their identities, and demand that $10 million be credited to their credit cards. Kudos to Susanna Cornett for her prescient early analysis.)

Still, the entire episode contains important lessons about terrorism and the best way to respond to it. After all, if a couple of lunatics could severely disrupt the entire capital region with a few random murders, what could a well-organized terrorist campaign do? And why were the public so terrified--terrorized, if you will--by a fairly small-scale random crime spree?

Two Washington Post opinion pieces published at the hight of the hysteria, by Paul Appelbaum and, earlier, by Marjorie Williams, argued that the extreme public fear stemmed from the lack of a clear pattern that can allow people to reduce (or simply to tell themselves they're reducing) their risk by taking certain precautions. "This killer seems especially frightening for his apparent determination to mirror, in the randomness of his acts, the brute impartiality of death itself," writes Williams. "This fear....is worse than most because of the unpredictability of the threat," writes Appelbaum.

No doubt that's part of the story. But unpredictable dangers--lethal diseases, freak accidents, or outbursts of violence--are hardly unfamiliar, and many of them (and certainly all of them together) are no rarer or more escapable than the DC sniper. Indeed, they are often less so; there was in fact a fairly established pattern of behavior on the sniper's part that suggested some obvious techniques for minimizing one's risk of becoming his next victim. What was particularly disturbing about the sniper, I believe, was that the mystery of his motive implied an open-endedness about the scale of the danger that he (or his kind) posed. Had he been known to be a typical psychotic, homicidally disgruntled crackpot, serial killer or even terrorist, DC-area suburbanites would have had some idea of the expected scale, frequency and targets of his actions; these are by now well-studied types whose behavior we can at least measure and assess, even if we can't understand (much less predict) it. But the cold-blooded distance-killers in this case seemed more like a new, previously undiscovered disease, with an unknown etiology--and no one had any idea how bad the epidemic could eventually get. How long would he continue? Would he ever get caught? Would there be copycats, and if so, how many? Would the danger spread elsewhere, or to other targets?

The optimistic flip-side of this observation is that as time goes on, and a fairly clear pattern of events emerges, with the killer either being captured, discontinuing his attacks, or continuing them at a constant or diminishing rate, such dangers eventually pass into the realm of estimable risks, and the anxiety they trigger thus declines. (Think of the case of Israel, where far worse atrocities occur regularly, with far less public reaction--indeed, often virtually no reaction at all, as one Israeli blogger recently reported.) Thus, though the mood of terror gripping the capital region may have been intense during the snipers' rampage, it is unlikely that a similar sequence of attacks will ever again have such a paralyzing effect. In fact, terrorism in general seems to suffer from this fundamental flaw--that societies inevitably develop a tolerance for shock, and more and more extreme (and thus difficult and dangerous) acts of violence are thus necessary to effect the intended level of fear and despair.

If this analysis is correct, then the DC-area and federal authorities may have erred by keeping such a tight lid on the details of their investigation. The existence and contents of multiple tarot-card messages, for example, may have frightened the public further had they been revealed; but they might also have, by creating a kind of public "profile" of the killer, contributed to a general sense of his knowability, even predictability, and thus dispelled some of the more open-ended scenarios (numerous co-ordinated terrorist cells, for instance) that contributed greatly to the public's fear. Should another serious terrorist attack (God forbid) occur, the authorities may want to keep this effect in mind, as they consider what to reveal about their investigation.