First of all, there was the timing: in concert, it seemed, with a sudden, deadly outburst of Al Qaida terrorist activity. Then there was the methodology: a strange combination of lone-nutbar tactics (cheesy, taunting warnings), extraordinary high-tech skill, and such meticulous planning and care that virtually no usefully traceable evidence has been found to date. And then there was the choice of victims: though all of Washington, DC was terrorized, the death toll was actually very small--a few random, unlucky souls who happened to be in the wrong place at the wrong time. And none of it fit any of the standard patterns: too impersonal for a typical serial killer; too indiscriminate for a revenge killer or a fanatic with an agenda; and too ineffective for a terrorist cell, which could no doubt easily cause far greater damage and mayhem--if those were really its goals--given the deadly techniques and skill levels it had displayed. It's no wonder, then, that although the FBI's primary hypothesis continues to characterize the perpetrator as a lone American-born male with a military background that provided him with the requisite skills, no solid evidence--let alone a culprit--has turned up to confirm or even support this guess.

I am referring, of course, to last fall's anthrax mailings. And one of the most conspicuous features of that spate of attacks, it should be recalled, was that it ended as quickly as it began--again, not fitting any of the typical patterns of a psychopath, domestic radical or foreign-based terrorist. I have a sneaking suspicion that the DC sniper will also suddenly halt his activities (if he hasn't already, now that the heat is on) and disappear without a trace. If so, then perhaps it is time to consider a new hypothesis: that some terrorist organization has decided to cheaply and anonymously generate periodic panics, rather than massive casualty counts.

The obvious next questions: "who?", and "why?"