With 1,000 FBI agents working the case of the Boston bombing, a suspect in custody and reams of evidence already sifted, there's quite a lot we've learned about the Tsarnaev brothers. The more we've learned, the less we really know. Consider:
1. So Russia told the FBI, twice, that Tamerlan Tsarnaev was a subject of interest to them. The FBI interviewed Tsarnaev and apparently obtained some of his communications and did not find any evidence that he was a threat. Then Tsarnaev goes to Dagestan, a place where many of the 9/11 co-conspirators received their training, for six months. But when he returned to the U.S., Russia once again pinged him, but did not provide any additional information. I say "but," because the Russian intelligence services have an enormous surveillance net and presence in the Caucasus; either they collected new information about his whereabouts or activities, or they did not. Significantly, whatever they DID find did not cause them to change their level of alarm. The U.S. intelligence and counter-terrorism analysts working the Tsarnaev case undoubtedly understand Russian capabilities better than I do. So what did the Russians know about the older brother BEFORE his Dagestan trip, and what did they learn from him during that trip?
2. Today came news that the two Boylston Street bombs were remotely detonated and contained a mix of different low-grade explosive powders. That points on one hand to a level of sophistication that might imply training or co-conspirators. But maybe not: A cellphone-triggered device is much harder to make than one that can be triggered by a fob-like device you can buy at a local hobby store. And the powder mix may simply have been a prudent way to avoid being seen as suspicious for buying lots of fireworks. In any event, making the bomb requires time, effort, and space. Where were the bombs made? Where were they tested? Were there precursors?
3. So far as motives go, we still don't have one. Radical Islamic jihad is a theology; the motive — to hurt people, to protest American foreign policy, to get back at someone — remains unknown. And that motive will help us determine the mix of factors that moved the older brother from apparently lapsed Muslim to radicalized Muslim to an active terrorist.
4. What are the differences between the goals of radical Islamic forces in Chechnya? Is there evidence that Russian separatism, ethnic nationalism has become less important? Is the Salafist-Sunni brand of radical Islam diversifying? Is it directly responsible for attacks against U.S. interests inside the United States? Have we missed signs that the Caucuses Emirate, with Doku Umarov as its spiritual leader, has aspirations to replace al Qaeda? (The group insisted this week it has no beef with the United States.) The brothers' Chechen family insists that Tamerlan was radicalized inside the United States. "Radicalization" is a very complex and rather undefined process. In shorthand, it seems to mean the social and psychological developments that created within him the justification to commit terrorism.
5. Finally, given that the frequency of terrorist incidents against the West is down, will the attention given to this incident fuel others who might have been otherwise convinced not to act on their radical beliefs?