Connection or coincidence? The FBI and Russian investigators have begun to plumb the potential links between former Gold Gloves boxer-turned-terrorist Tamerlan Tsarnaev and a now-dead Canadian boxer-turned jihadi named William Plotnikov. Plotnikov fought in Dagestan for an Islamist terrorist network and was killed by Russian forces just days before Tamerlan returned to the US. CNN has more on Plotnikov:

The New York Times reported yesterday on the interest in Plotnikov, but also that Russian investigators now seem pretty sure that Tamerlan’s six-month sojourn wasn’t just intended to catch up with family:

On Saturday, the Russian investigative newspaper Novaya Gazeta reported that Mr. Tsarnaev had sought to join the Muslim insurgency in Dagestan and had been in contact with several rebels who were killed by Russian authorities in late spring of 2012 while he was staying in Makhachkala, the regional capital. Mr. Tsarnaev left Dagestan in July 2012, just two days after a shootout between militants and the police in which several militants were killed, including William Plotnikov, 23, a Russian-born Canadian. Investigators are trying to determine whether Mr. Tsarnaev and Mr. Plotnikov met, one official said on Sunday. …

Experts on the effort by Russian authorities to contain the Muslim insurgency in Dagestan and elsewhere in the North Caucasus region said that if officials were aware of Mr. Tsarnaev’s arrival in Dagestan in January 2012, he probably would have been under scrutiny throughout his time there.

Under this theory, Plotnikov — or his network — might have been recruiting Tamerlan to fight in Dagestan when the network got taken down by the Russians, which led Tamerlan to return to the US. That doesn’t make a lot of sense, however. Presumably, these particular terrorists in Dagestan thought of the Russians as their biggest enemy, and if they had convinced Tamerlan to fight, it would have been against the same Russians.

But would Tamerlan have agreed to stay there to fight in the first place? He had a wife and child in the US, whom he left behind for six months to travel to Dagestan for some reason; if he wanted to stay, why not bring them with him? It seems a little more likely that if Tamerlan was making contact with these terror networks, it was to be able to return to the US to carry out their attacks.  The reason he would have fled after the raid that killed Plotnikov is (a) to avoid getting arrested if Russians connected him to the group, and (b) to conduct his attack against the US. The timing could still be coincidental, but the “coincidences” are beginning to stack up.