The details that have emerged so far suggest there are still institutional gaps that could be fixed to bolster the U.S. counterterrorism system. The bombings also exposed a less-reassuring reality: Even when defenses function as designed, they can be undermined by factors beyond their control. In Boston, some of those factors were as fundamental and elusive as timing and luck. “When this happens, there's sort of an automatic response to find a linkage to failure,” said Andrew Liepman, who served as deputy director of the National Counterterrorism Center until last year. It's perfectly reasonable to look into whether there were breakdowns, Liepman said. “But that massive counterterrorism infrastructure works amazingly well to protect the country. We need to get used to the idea that it isn't foolproof.”
It has been more than a decade since the U.S. began building its massive counterterrorism infrastructure, an apparatus that has been reconfigured several times after a series of near-miss attacks, says the Washington Post. he strike in Boston marked the first time that a terrorist bomb plot slipped past those elaborate defenses and ended in casualties. Whether that outcome represents an intelligence failure is already the focus of a multi-agency review as well as a heated political debate.