The U.S. needs to rethink our overall nuclear strategy. Our current strategy is still based on fighting a nuclear war with Russia. We should refocus it, and stop spending billions on an obsolete U.S. nuclear arsenal and move at least part of those funds to preventing ISIS or any other group from getting their hands on radioactive materials. It's time to stop fighting Soviets and shift our funds to fighting the terrorists that truly threaten us. The risk of ISIS getting their hands on nuclear or radiological weapons is small, but it is not zero. And that is too big of a gamble to take when American lives are on the line.