The Boston bombings were reminiscent of another recent near-miss, the failed attempt in 2010 by a Pakistani American to ignite a bomb hidden in a car in Times Square. Faisal Shahzad had lit the fuse on a device that also involved a pressure cooker. A nearby food vendor noticed smoke and alerted authorities, and Shahzad was apprehended after boarding a plane bound for Dubai.
Boston was far from defenseless as the marathon got underway. Among major U.S. cities, only New York and Washington have been under more stringent security since the Sept. 11 attacks.
Boston has used federal grants to help assemble a surveillance network that employs hundreds of cameras across the city and throughout its subways. Those cameras, along with images captured by private video systems and spectators' cellphones, helped authorities identify the Tsarnaev brothers as suspects — but only after three people had been killed and more than 170 others injured.
Schiff said the bombings may trigger new debate over whether surveillance systems such as Boston's should be expanded, whether spy agencies should focus more resources on regions such as Chechnya and whether the United States needs to examine how it integrates disaffected immigrants.
"We've had a lot of successes in degrading the ability of al-Qaida to launch massive attacks, but we've had a proliferation of one-off, foreign-born plots and self-radicalized individuals," Schiff said. Ultimately, he said, "we're going to have to recognize a certain vulnerability, and adopt a determined view that we will go on as we have, taking prudent precautions, but not changing the way we live."