Here I distinguish the four logically possible ways in which nuclear weapons might be used: in an all?out nuclear strike, either first or second; or in a limited strike, either first or second. I go on to show that neither of the two most basic moral perspectives, consequentialistic or deontological, would permit nuclear weapons to be used in any of those four ways; nor would they permit an empty threat to use them. Nuclear weapons are thus shown to be morally (...) useless. Given the moral opportunity costs of maintaining this morally useless arsenal, nuclear weapons should therefore be abandoned, universally if possible and unilaterally if need be. (shrink)