"Beginning in 2010, the United States orchestrated broad international economic pressure on Iran to persuade it to agree to strict limits on the program--pressure that contributed to the June 2013 election of the relatively moderate Hassan Rouhani as president of Iran and the eventual negotiation of a 'Joint Comprehensive Plan of Action' (JCPOA). The JCPOA, which began formal implementation on January 16, 2016, exchanged broad sanctions relief for nuclear program limits intended to ensure that Iran would require at least a year to produce a nuclear weapon after a decision to do so. President Obama asserted that the implementation of the JCPOA presented an opportunity to construct a new and more positive U.S. relationship with Iran. However, Iran has continued to test ballistic missiles; maintained support for regional movements such as Hamas, Lebanese Hezbollah, and Houthi rebels in Yemen; arrested additional U.S.-Iran dual nationals; and conducted high speed intercepts of U.S. naval vessels in the Persian Gulf. The Trump Administration has characterized Iran as an adversary of the United States and stated a commitment to countering Iran's regional influence--although without taking steps that would conflict with U.S. commitments under the JCPOA. The Administration has not articulated a hope or intent to develop an improved relationship with Iran [...] The United States has supported programs to promote civil society in Iran, but successive U.S. Administrations, including the Trump Administration, have stopped short of adopting policies that specifically seek to overthrow Iran's regime."
CRS Report for Congress, RL32048
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html