Military options, on balance, remain uncertain in their ability to end Iran’s quest for nuclear weapons or even significantly delay their acquisition, absent sustained bombing of a wide range of military and nuclear targets. It is doubtful that a surgical strike against a few nuclear facilities can succeed in slowing an Iranian effort to obtain an atomic bomb. Military strikes invite retaliation and increase the chance of a regional military confrontation that risks severely damaging U.S. and its allies’ interests. As such, military options are rightly viewed as a last resort. Despite their risks they have not been taken off the table by the U.S. government.