Important thing here is to try and find out what made these 2 brothers (1 a medical student) carry out such evilness against a country which welcomed them from Chechnya 9 years ago.
I'm sure the authorities will be working hard to get to the root of the problem. I'd be surprised if they were working alone. How many sleeper cells run by the same organisation are currently hiding in the USA? The FBI needs to get as much info on this as possible.
Hopefully they can keep him alive just long enough to extract the information they require...then both brothers can rot in hell. The only good terrorist is a dead terrorist.
What happened in Boston was tragic......but it could have been a whole lot worse given the amount of people who were gathered in those areas. The death toll could have ran into 100's.
My sympathies go out to everyone effected by this callous act.