U.S. invasion of Iran’s neighbors

The difficult relations between Iran and the United States grew more complex in the wake of the September 11, 2001, attacks on the World Trade Center in New York City. The events that followed those attacks saw a level of converging interests—and even cooperation—between the two countries, though the deep enmity between the two also led Iran to simultaneously work to prevent the United States from gaining a firm foothold in its vicinity. Iran, which had been supporting the Northern Alliance against the Taliban since 1998, facilitated the U.S.-led toppling of the Taliban even while opposing U.S. occupation of the country. Cooperation over Afghanistan opened dialogue among the mid-level echelons of Iran and the United States, marking a peak in their relationship. This tacit rapprochement was strained in January 2002, when U.S. Pres. George W. Bush in his State of the Union address categorized Iran as a member of the “axis of evil” (with the regimes of Iraq and North Korea, whom he also described as seeking weapons of mass destruction), an association that was immediately condemned in Iran. U.S. plans for a military intervention in Iraq, a move criticized by President Khatami for its potential to increase instability in the region, also strained the relationship. Still, Iran took advantage of the ouster of its adversaries Saddam Hussein and his Baʿath Party to advance pro-Iran Shiʿi interests in Iraq. Though Iran, like the United States, favored the establishment of a democracy in the Shiʿi-majority country, Iran promoted an insurgency through groups such as Muqtada al-Sadr’s Mahdi Army and the Badr Organization.

Nuclear program and sanctions

Among the most contentious of Iran’s foreign policy issues at the beginning of the 21st century was the ongoing question of the development of its nuclear capabilities. Iran’s nuclear program became the focus of international attention in 2002 when an Iranian dissident group revealed that Iran was secretly constructing a uranium-enrichment facility and a heavy-water reactor. Iran insisted that its nuclear pursuits were intended for peaceful purposes, but the international community, expressing deep suspicion that Iran’s activities included the development of nuclear weapons, advocated efforts to suspend them. International pressure led to a partial suspension of Iran’s nuclear program in 2003, but the nuclear issue returned to the forefront after the election of Ahmadinejad in 2005, when Iran resumed nuclear activities and began to set new limits on its cooperation with the International Atomic Energy Agency, the international organization responsible for inspecting nuclear sites. International talks failed to convince Iran to suspend its activities again, so in 2006 the UN Security Council passed the first of several rounds of sanctions targeting the nuclear program. Ahmadinejad, a staunch defender of Iran’s right to perform nuclear research, indicated the country’s intent to continue its nuclear activities despite both incentive packages and sanctions put forth by the international community. A National Intelligence Estimate (NIE) report issued by the U.S. intelligence community in December 2007 indicated with high confidence that Iran had halted its nuclear weapons program in 2003 and assessed with moderate confidence that work had not resumed by mid-2007. However, in February 2008 the International Atomic Energy Agency suggested that there existed evidence that Iran had in fact continued nuclear development after the 2003 date put forth by the NIE. Tensions were raised further by Iran’s highly publicized tests of medium- and long-range ballistic missiles and by the revelation in 2009 that Iran was secretly constructing a heavily fortified underground uranium-enrichment facility near the city of Qom. Those developments were followed by a new round of UN sanctions, as well as sanctions by the United States and the European Union (EU) targeting Iran’s oil and natural gas industries.

Nuclear deal reached: Joint Comprehensive Plan of Action

The election of Hassan Rouhani as president in June 2013 brought about a shift in Iran’s handling of the nuclear issue. Rouhani had campaigned on a promise to restart international negotiations with the goal of reducing sanctions on Iran, and, upon taking office, he embarked on a diplomatic effort to improve Iranian relations with the West. A speech by Rouhani at the UN General Assembly in September 2013 that struck conciliatory notes was followed by a telephone conversation with U.S. Pres. Barack Obama, the first direct dialogue between a U.S. and an Iranian leader since 1979. Negotiations between Iran and a group comprising the United States, China, Russia, France, Germany, and the United Kingdom began in early November 2013, and by the end of the month an interim agreement had been reached that placed restrictions on Iranian nuclear activities in exchange for a temporary reduction in sanctions. Negotiations progressed slowly, requiring the term of the interim agreement to be extended several times.

In early April 2015 both sides agreed to a framework that outlined some aspects of a final agreement. Under the framework, in exchange for the reduction of sanctions, Iran would give up 98 percent of its highly enriched uranium, and its uranium enrichment and nuclear research would be restricted and monitored. In a major concession, the deal would exclude restrictions on Iran’s ballistic missiles program and other conventional arms, though the U.S. would not be obligated to lift its sanctions on aspects not covered by the deal. A final agreement, known as the Joint Comprehensive Plan of Action (JCPOA), was reached in July 2015 that largely followed the terms of the earlier framework, requiring Iran to reduce its nuclear stockpile and allow the International Atomic Energy Agency to inspect its nuclear facilities in exchange for the progressive reduction of sanctions. In January 2016, international economic sanctions on Iran were lifted after the UN said that it was satisfied with Iran’s progress in implementing the terms of the agreement.