Only 18 months into his Presidency and nuclear arms control has become a defining feature of Donald Trump’s Administration. On May 8, 2018, he announced America’s withdrawal from the Iran nuclear deal, the Joint Comprehensive Plan of Action (JCPOA). A month later, on June 12, 2018, he concluded an agreement in Singapore with Kim Jong Un working towards denuclearisation of the Korean penninsula. And in July 2018 he met with Russian President Vladimir Putin in Helsinki, which included discussion of the 1987 Intermediate-range Nuclear Forces (INF) Treaty and 2010 New START Treaty, according to Russia’s ambassador to the United States, Anatoly Antonov. And as with all areas of policy, Twitter has come to play a role in Trump’s handling of nuclear issues, often resulting in mixed messages and confusion among adversaries, allies, and within the Administration.