Fifty years ago the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), an international agreement that seeks to limit the spread of nuclear weapons, went into effect. Under the NPT, all countries party to the treaty are permitted to develop nuclear technologies for peaceful activities, but countries without nuclear weapons are not permitted to divert those technologies to manufacture nuclear weapons. In 2003, it was determined that Iran had pursued nuclear weapons under the guise of its civilian nuclear program, violating its NPT commitments. Unified international economic sanctions brought Iran to the negotiating table, resulting in the Iran Deal, formally termed the Joint Comprehensive Plan of Action (JCPOA), signed in 2015. The Iran deal placed additional limits beyond NPT restrictions, on materials and activities that could be diverted to developing a nuclear weapon, extending the time needed for Iran to develop a nuclear weapon from a few months to roughly a year. This changed when the United States unilaterally withdrew from the JCPOA in May 2018 and Iran announced the following year that it would no longer be bound by the terms of the deal. Lacking the added restrictions of the Iran deal, Iran has begun ramping up domestic nuclear activities, raising fears that they may pursue development of a nuclear weapon. The United States has several policy options available in seeking to forestall such an outcome. This article discusses the advantages and disadvantages of several of these options, including economic sanctions, counterproliferation military action, or return to the JCPOA or a similar diplomatic agreement. The return to a cooperative agreement such as the Iran deal, though made challenging by mutual distrust, is assessed to provide the best chance to prevent Iran from resuming a nuclear weapons program.