TV news keeps talking about technical assistance in bomb making for the Boston bombers. Interesting and all, but to my way of thinking, not all that important.
Important, is how the brothers converted from reasonably successful immigrants into terrorist bombers. Did someone preach Jihad to them? Is it possible for just internet websites to turn reasonable people into bombers? Without a live person to spread the message? Are the brothers more pliable than anyone I know?
Anyhow, I'm more interested in motivation, what turned the brothers into bombers, than I am in how they built the bombs.