University of Notre Dame
Kroc Institutde for International Peace Studies

Kelsey Davenport is Director for Nonproliferation Policy at the Arms Control Association.

Donald Trump faces a tough array of foreign policy challenges, but noticeably absent from that list is the threat of a nuclear-armed Iran. If Trump plays his cards right, he can keep Iran’s nuclear program off the table for the duration of his presidency. But that will require supporting, not disrupting, the highly-effective multilateral nuclear agreement the United States and its partners reached with Iran in 2015.

Before following through on threats to tear up the agreement or renegotiate it, Trump should review the Iran deal’s scorecard for the past 18 months. The facts show that the deal is working: Iran’s pathways to nuclear weapons remain blocked and its limited nuclear activities are strictly monitored.

To meet the deal’s limits, Iran shipped out 98 percent of its stockpile of enriched uranium and put more than 13,000 centrifuges, which are used to enrich uranium, in monitored storage.

For more than a year, Tehran has limited its uranium enrichment to power-reactor grades well below the level necessary for a nuclear bomb. Iran only operates 5,060 centrifuges and abides by a strict cap on its stockpile of enriched material.

As a result of these restrictions, if Iran chose to pursue nuclear weapons, it would take them more than 12 months to produce enough material for one bomb. In 2013, that time was 2-3 months and shrinking. The expanded timeline, which will remain in place for the next decade, gives the international community time to respond if Iran breaches the agreement and pursues nuclear weapons.

Under the deal, the international community also stands a much better chance of quickly detecting any illicit nuclear activities in Iran. For the first time, International Atomic Energy Agency (IAEA) inspectors have regular access to all of Iran’s nuclear sites and are using real-time surveillance to monitor key facilities and enrichment levels around the clock. The IAEA’s quarterly reports show Iran is abiding by these commitments.

Iran is also re-designing its unfinished reactor under international supervision so it will not produce meaningful amounts of weapons-grade plutonium. U.S. scientists have reviewed the plans and confirmed that the new reactor will not pose a proliferation risk. The deal has also demonstrated its resilience. Like any complex agreement, it could not anticipate every technical challenge that might arise. But the agreement created a joint commission with a dispute resolution mechanism to address issues as they emerge. Over the past year, the commission has dealt with several ambiguities and technical challenges, preventing them from becoming proliferation concerns that could threaten the success of the agreement.

These critical restrictions and monitoring measures will be lost if Trump scraps the deal. While Iran will remain bound by treaty obligations not to pursue nuclear weapons, policymakers in Tehran have already said the country will ramp up its nuclear activities if Washington abrogates the agreement. That could include reinstalling stored centrifuges, enriching uranium to levels closer to weapons grade, and limiting inspector access. These steps will likely reignite international uncertainly about whether Iran’s ultimate intention is a nuclear weapons program.

If Trump wants to take a proactive approach toward Iran and put his own stamp on the deal, there are policy options that could strengthen and complement the agreement without risking its successes. Building upon the deal is also likely to be supported by Washington’s negotiating partners (China, France, Germany, Russia and the United Kingdom), whereas scrapping the deal and renegotiating is a nonstarter.

First, Trump should ensure that the IAEA has the resources necessary to monitor Iran’s compliance. That includes investing in U.S. national laboratories to support the development of next-generation verification technology for international inspectors.

Additionally, the administration should look for opportunities to extend and expand core nuclear limitations in the deal. Many innovative restrictions, such as monitoring uranium mines, real-time tracking of uranium enrichment levels, and capping stockpiles of nuclear materials, expire in 15-25 years. The Trump administration could explore options for adopting these measures at the regional or international level. If these provisions become the new norm, it would lock in more permanent restrictions on Iran and strengthen nonproliferation efforts writ large.

The deal also prohibits Iran from using certain types of explosives relevant to detonating a nuclear warhead. Encouraging other states with the means to produce nuclear material to accept a similar prohibition would provide a further bulwark against weapons development.

The nuclear deal did more than just restrain Iran’s nuclear activities, it reinforced the international community’s resolve to prevent the rise of new nuclear-armed actors. Failing to support and build on the deal would be a missed opportunity to strengthen nonproliferation.