At a research facility some two dozen miles from the White House, government scientists operate a nuclear reactor burning uranium that could be used to build a nuclear weapon. A similar research reactor sits just blocks from where the suspected Boston Marathon bombers gunned down a campus policeman. A third reactor is located in the Midwest, less than a mile from a 71,000-seat college football stadium.

Yet more than a decade after the Sept. 11 attacks, these facilities “are particularly vulnerable to sabotage attack” and are not required to meet tougher standards used by the military to protect its weapons-grade uranium from terrorists, say the authors of a new Pentagon-funded study.