Moreover, Obama can point out that a cost-benefit analysis of foreign policy, and in particular of prospective foreign wars, will not be a bad idea. Not one of America's wars until now was subjected to a serious public assessment of its likely cost ahead of time. Had such an assessment been applied to the wars in Vietnam, Afghanistan, and Iraq, better policy decisions might have been made. Other wars, most notably World War II, would have survived the scrutiny and gone forward.