I hate to say that but good old KGB seems to have these roaches under control. Canadian jihadi was interrogated by KGB and given them a lot of info back then. As son as they turned more radical both Canadian and Tsarnaev along with Palestinian Mahmoud Nidal seems to have been abducted by KGB in July 2012 and strongly advised to go back home: “We don’t need you stinking amateur American jihadis. Go back home, have burger and let your stinking FBI deal with you, suckers”. These guys probably thought: “Screw it, we are tough jihadis”. Nidal was first to die, Canadian next. Tsarnaev finally got his message and flew back to Boston in just three days after Canadian’s death.
Yes, it’s possible Putin was behind it.
KGB is not concerned with PC insanity like our intelligence bureaus have become under Obama. Obama is the ‘weak horse’ .