President Trump’s decision to withdraw from the nuclear agreement with Iran will undermine U.S. power and influence around the world. Congress must closely monitor the reinstatement of sanctions on Iran to reduce the blowback on U.S economic interests, and provide strict oversight of the Trump administration’s evolving strategy toward Iran.

The Iran nuclear deal was officially implemented on Saturday, as Iran successfully fulfilled its initial key nuclear commitments and the international community relieved major sanctions, including unfreezing about $100 billion of Iranian money. Implementation Day was met with applause from deal supporters in the U.S. and Iran, while critics have raised questions about whether Iran will adhere to its requirements and how it will flex its newfound economic power. Also in recent days, the U.S. and Iran agreed to a prisoner swap that led to the freedom of Washington Post reporter Jason Rezaian and others, and negotiated the release of American sailors detained in Iran. What does the arrival of Implementation Day mean for Iran’s nuclear program and nuclear nonproliferation, and how does it bode for the future of U.S.-Iran relations? We asked Belfer Center experts to weigh in on these and related questions.

Ayman Khalil asked whether the effort to create a WMD-free zone in the Middle East is dead. Martin's answer is this: The effort will continue, but the opportunity presented by the 2010 Review Conference for the Nuclear Non-Proliferation Treaty (NPT) may be slipping out of reach.

As negotiations with Iran over the future of its nuclear program inch toward a possible deal, another intractable Middle East problem with a nuclear dimension is likely to start getting more serious attention. It is the question of whether there is any chance that Israel, Iran, and their Arab neighbors will agree to discuss establishing a regional zone free of all nuclear, biological, and chemical weapons and their delivery systems. After decades of backsliding, proliferation, and conflict in the Middle East, the conventional wisdom says the current round of efforts will fail. I think the conventional wisdom is wrong.