A new study is casting fresh doubt on the Obama administration’s so-called “missile defense” system. Researchers at MIT and Cornell say the Pentagon made false claims about the success rate of tests of a key weapon known as the SM-3 last year. The military claimed the SM-3 had intercepted 84 percent of incoming targets during the tests. But a new evaluation says the missiles had a success rate of only ten to 20 percent. Study co-author and former Pentagon adviser Theodore Postol said, “The system is highly fragile and brittle and will intercept warheads only by accident, if ever.” President Obama criticized the missile system during his run for the White House but has since touted it since taking office.