President Donald Trump has now assumed control over the nation’s arsenal of more than 4,000 nuclear weapons. What will he do with them? We do not yet know the Trump administration’s approach to nuclear strategy, but Trump has offered some clues to his mindset. He has denounced nuclear arms control, declaring that he would welcome a renewed nuclear arms race with Russia. He has indicated that he might be willing to allow Japan and other U.S. allies to acquire nuclear weapons. And he has suggested that he might be willing to use nuclear weapons against the Islamic State.