Why Law Enforcement Wants Boston Bombings Suspect No. 2 Alive

The mysteries of the Boston Marathon bombings will be a lot easier to unravel if authorities are able to capture rather than kill Dzhokhar Tsarnaev, 19, a suspect in the explosions Monday that killed three and injured and maimed some 170 others. His older brother, Tamerlan Tsarnaev, 26, suspect No. 1, died early Friday in a shoot-out with police. Law enforcement officials are also looking for other people in connection with their investigation.

The brothers are from a part of Russia near the rebellious province of Chechnya, and made clear on social media that they were proud to be of Chechen heritage. They told a hostage they held briefly during a Thursday-night carjacking that they were the Marathon bombers, according to NBC News.

If so, what was their motive? Were they trying to make a political or religious point?

Who were they working with? Are they part of a larger conspiracy?

Tamerlan was a boxer who had applied for U.S. citizenship, but his aunt in Toronto said he became more religious a couple of years ago and started praying five times a day. Dzhokhar was also Americanized, and became a citizen on last year -- on Sept. 11. What happened to turn the suspects against their adopted country?

Where did they learn how to make the bombs?

How much time did they spend plotting the attacks?

Why did they target the Boston Marathon? Was there any significance to that event, or the fact that it was held on Patriots’ Day? Or were the brothers simply interested in a big crowd conveniently close to where they lived?  

Where did Tamerlan go when he left the country for six months in January 2012, and what was he doing?

Where did the brothers get their guns, and would any of the measures under discussion in Washington have prevented the gun purchases?

Did they really think they wouldn't get caught?