What Will Trump or Harris Do if Iran Goes Nuclear?

America’s intelligence chief recently warned that Iran is preparing to take the final steps to produce a nuclear weapon, making it now mostly a matter of Tehran’s choice if and when to do so.

Preventing this outcome must be an immediate issue for the next president. With Iran on the nuclear precipice, the next commander-in-chief will have no time, and little margin for error, as he or she also must staff a new administration and confront countless other priorities.

On the eve of their first head-to-head debate, our new report from the Jewish Institute for National Security of America lays out the urgency for a serious plan to start addressing this threat the moment either candidate assumes office.

Though less appreciated, Iran’s improving capacity to keep churning out fissile material is no less important. It can now fully crank out eight bombs’ worth of 90 percent enriched uranium in just one month, and another four in the following couple months. Today, Iran could amass an arsenal’s worth of fissile material in the same timeframe it needed to produce just one bomb’s worth when President Biden was elected.

As the recent U.S. intelligence assessment suggests, there are growing indications Tehran could be closing in on the final element of a bomb: a nuclear explosive device. Israel’s covert seizure of Iranian nuclear archives in 2018 laid bare how Tehran systematically outpaced the world’s assumptions about its weaponization progress. And just this summer, American and Israeli intelligence revealed Iran’s new research and simulations of nuclear detonations.

In parallel, regime officials increasingly advertise their ability and readiness to weaponize if provoked – a marked and abrupt rhetorical shift from years of Tehran’s self-righteous insistence that its nuclear program was purely peaceful and civilian in nature.

Iran has obscured much of this progress by violating its safeguards agreements with impunity. Since 2021, it has rolled back access by IAEA inspectors to its enrichment-related sites. For even longer, it has blocked inspectors from pursuing new leads, drawn from Israel’s archives seizure, regarding weaponization. Throughout, the IAEA director has sounded alarms about his agency’s inability to track Iran’s expanding nuclear program, including potential clandestine capabilities.

These factors combine to make Iran’s eventual achievement of nuclear weapons capability seem inexorable absent a change in course. Yet the current administration prefers to avoid anything that risks near-term tensions with Tehran, even if this courts much greater future risks. For the same reason, neither presidential candidate has offered a clear alternative strategy, nor have they drawn serious attention to the problem.

Staying this course will be more freefall than autopilot as Tehran’s ongoing progress further contradicts core U.S. commitments and rings increasingly hollow in the ears of friends and foes around the world. It also will embolden Iran to continue deepening ties with other U.S. adversaries and destabilizing the Middle East, in turn compounding the existing challenges confronting American leadership and credibility in overlapping crises from Europe to the Indo-Pacific.

The next administration will inherit this deteriorating deterrence deficit, with precious little time before October 2025, when it loses a key remaining lever to rebuild international pressure by “snapping back” UNSC sanctions that have lapsed steadily since 2020.

Vice President Harris and former President Trump must explain how they plan to fulfill America’s consistent, bipartisan pledges across six Presidential administrations to prevent a nuclear Iran. Debate moderators should put the issue squarely before the candidates, asking if they would order military operations if presented with credible intelligence that Iran is on verge of acquiring nuclear weapons.

Though risky, uncertain, and demanding, tackling this worsening crisis is still preferable to the alternatives in an already-dangerous world for U.S. interests, leadership, and credibility that are increasingly in doubt globally. With November 5 right around the corner, preventing a nuclear Iran is also imperative to address what a resounding majority of voters see as a major national security threat.

Ambassador Eric Edelman is the former Under Secretary of Defense for Policy.

Gen. Charles Wald, USAF (ret.), served as the deputy commander of U.S. European Command. They co-chair the Iran Policy Project at the Jewish Institute for National Security of America (JINSA), where they are Distinguished Scholar and Distinguished Fellow, respectively. 

Jonathan Ruhe serves as Director of Foreign Policy at JINSA.