So far, and in spite of the American media's best effort to acquaint its audience with a country called Chechnya (and the Czech embassy's best efforts to remind that audience of the excellence of Bohemian pilsner), there is little evidence linking the Boston marathon bombings to any jihadist organization or cell headquartered in the North Caucasus. CNN cited an unnamed U.S. official versed in latest intelligence who said that the Brothers Tsarnaev had no discernible association with al-Qaeda, its affiliates, or any entity that may pose a "significant terrorist threat to the United States." The Mujahedeen of the Caucasus Emirates, the main Salafi-jihadist franchise in the region, headed by Doku Umarov and responsible for previous attacks on the Moscow subway and Domodedovo airport, denied any affiliation to the Tsarnaevs or the Boston bombings. The Caucasus Emirate, the group insisted in a published statement, was only "at war" with Russia, not the United States. Russia's branch of Interpol appears to agree; it possesses no information that would implicate the young Chechens in the Caucasus Emirates. Other anonymous Russian security sources have similarly disclaimed ties between Umarov and the Tsarnaevs.
Nevertheless, and in spite of a growing counterterrorism consensus that "lone wolf" attacks will proliferate as the capacity of organized global jihadist networks is steadily diminished, the search for a clerical-guerrilla patron behind the Tsarnaevs continues. Dzhokhar, the younger brother now in custody, has left only a tenuous data trail on his VKontakte profile, citing his interests as "Everything about Chechnya," "Chechens," "Mosques" and "Islam." (The bit about the highest priority being "career and money" is perhaps too befitting of an exclusively American psycho.) So far, most journalists have seized upon the FBI's statement that:
In early 2011, a foreign government asked the FBI for information about [elder brother Tamarlan] Tsarnaev. The request stated that it was based on information that he was a follower of radical Islam and a strong believer, and that he had changed drastically since 2010 as he prepared to leave the United States for travel to the country's region to join unspecified underground groups... The FBI interviewed Tamerlan Tsarnaev and family members. The FBI did not find any terrorism activity, domestic or foreign.
The foreign government is Russia's. Yet if the Federal Security Service (FSB), knew in 2011 that Tamerlan had become an extremist, why did it let him travel to Russia in 2012 and stay in one of the most volatile and Islamist-dominant regions of the country? As Anna Nemtsova has noted, 67 people died from terrorist attacks in Dagestan in the first four months of this year; the weekend before America awoke to discover another one of its major cities convulsed by panic and fear, Russian tanks and artillery had pummeled a tiny hamlet of 4,000 in Dagestan, forcing hundreds to flee to a neighboring town. The elder Tsarnaev managed to stay in Makhachkala for six months, visiting relatives, without (so far as we know) being detained or interrogated by local Dagestani authorities or Russian police. The Dagestan Interior Ministry says that neither Tamerlan nor Dzhokhar was ever in its database, which must be promiscuously large. If Tamerlan joined any "underground groups" or jamaats, then he did so under the nose of more than one state apparatus, and no group seems eager to want to claim him as one of their own.
The likelier explanation for what happened in Boston is that Tamerlan Tsarnaev started becoming a convert to jihadism during his time in the United States, and decided to take his impressionable younger brother with him. An apparent prompt or accelerant in this process was his tutelage by "Misha," an Armenian convert to Islam whom the Tsarnaevs' stateside relatives have identified as the person who radicalized Tamerlan. Still another catalyst may have been his virtual exposure to fellow boxer Feiz Mohammad, a Salafi sheikh based in Sydney who has made familiar noises about raped women, Jews, and non-believers. (Australia's attorney general has taken to the airwaves to argue that the sheikh has been rehabilitated; I'm not sure the attorney general can really know that, but the point is how many more unannounced followers of Feiz Mohammed's more outspoken former self are currently lurking around various YouTube channels and chat forums.)
Finally, Tamerlan's time in Dagestan, where his mother apparently encouraged his piety, likely contributed to his indoctrination in extremist ideology, which usually happens along a continuum. Indeed, a preliminary scan of the brother's cell phones and computers suggests no accomplices, and the captured Dzhokhar has told investigators that the boys learned how to build pressure cooker bombs by reading Inspire, the late Anwar al-Awlaki's how-to guide for would-be jihadists.