Excerpt:
With a few lucky breaks, last week's Boston Marathon bombing could have had a dramatically different outcome. Had Tamerlan or Dzhokhar Tsarnaev sought help building their bombs on jihadist web forums, FBI agents likely would have detected it.
They would have sent in an undercover operative or an informant. And the Tsarnaevs would have been arrested as they tried to detonate their bombs, which had been rendered inert by the FBI.
And it would have elicited howls of protest from Islamists and their supporters.