I have a feeling that intergovermental relations between the US and Russia are going to cool quite soon, based upon Occam-razor-based speculation:
1) One striking thing about the Boston Marathon bombing was that both bombs worked, and worked quite well – they were compact, highly effective, and detonated with great timing. Someone really knew what they were doing in that sense and apparently it isn’t easy to make a good bomb like that – you either have to have experience or good training/instructions.
2) When the news reports came out that the suspects were immigrants who were ethnically Chechen – that made sense given how good some Chechens became at making bombs aimed at Russia in the past 2+decades.
3) Turns out that the older brother Tsarnaev travelled to the Russian Chechen area in 2010, and even before he left, Russian intelligence asked the FBI to question him about “underground groups” and “radical islam”:
The FBI also said that it requested but did not receive more specific or additional information from the foreign government.
4) Now ask yourself: which Chechens do the Russian FSB track so closely that they can figure out the going-on of some random guy living in America – people who dig “radical islam”? Maybe, but my guess is that they care most about anyone remotely associated with the insurgency who know, e.g., how to build bombs like those in the wave of bombing that hit Russia in the recent past.
5) Given what they knew and when, surely the FSB kept tabs on him while in Russia and who he hung out with. And since it appears like he knew how to build a darn good bomb (without otherwise appearing to be criminal mastermind), that implies he hung out/intensively communicated with people who knew about those things! The FSB must have known something was wrong, (either that or Russia may be in for a big surprise in the near future).
6) I suppose that the FBI could be lying about this, but I can’t imagine that in 2010/2011 that if the FBI had any inkling that Tsarnaev might be building a bomb, that they wouldn’t follow him and make an arrest after he started buying substantial quantities of black powder – this should have all been over in 2012.
But instead we get mayhem and resulting idiot politician wanting to torture 19-year olds.
I don’t have to be politic as this erudite fellow; so here’s a one-fingered salute to you, Russian FSB!