It is clear from his reckless decision to pull out of the Iranian nuclear deal, as well as his statements during the campaign and since coming into office, that President Trump does not understand the purpose of arms control agreements.
The purpose of the Joint Comprehensive Plan of Action (JCPOA), i.e. the Iran deal, was to prevent Iran from developing nuclear weapons. While the United States, the other five signatories to the deal, and most of the international community would like Iran to make other changes in its national security policy, these other actions, like developing ballistic missiles or helping keep Assad in power in Syria, are not part of the nuclear deal. Can one imagine what would have happened if the US had pulled out of the Strategic Arms Limitation Agreement (SALT I) and the Anti-ballistic Missile (ABM) treaty with the former Soviet Union, which were negotiated by the Nixon administration in 1972, when the Soviets invaded Afghanistan in 1979 or continued to oppress their Warsaw Pact allies?The above excerpt was originally published in Bulletin of the Atomic Scientists.