Why Law Enforcement Worked So Hard to Take Boston Bombings Suspect No. 2 Alive

The mysteries of the Boston Marathon bombings should be a lot easier to unravel since authorities involved in a massive manhunt managed to take Dzhokhar Tsarnaev into custody Friday night without killing him.

Tsarnaev, 19, a suspect in the explosions Monday that killed three and injured and maimed some 170 others, was taken to the hospital in serious condition. His older brother, Tamerlan Tsarnaev, 26, suspect No. 1, died early Friday in a shoot-out with police.

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.

Several law enforcement officials at a post-capture press conference mentioned how happy they were that they were able to take Tsarnaev into custody alive. They said that's always the first preference because it will ensure accountability to the victims. As President Obama put it in a statement to cameras, "The families of those killed so senselessly deserve answers. The wounded, some of whom now have to learn how to stand and walk and live again, deserve answers."

Authorities will want to learn first off from Tsarnaev whether any other explosive devices exist, and if so, where they are. Among the many other unknowns:

What was the brothers' 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? "Why did young men who grew up and studied here as part of our communities and our country resort to such violence?" Obama asked.

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?