Understanding a Crisis: Iran, Israel and the United States
The dramatic escalation of tensions between Iran, Israel and the United States in 2025 has captured global headlines. These developments raise urgent questions about U.S. foreign policy, nuclear diplomacy and the role of international law.
This page features timely analysis from leading experts at The Fletcher School on the latest developments, implications for global security and potential paths forward for diplomacy and security. Explore faculty commentary and media coverage to better understand what’s at stake in the evolving relationships between the U.S., Iran and Israel.
For interview opportunities with Fletcher faculty, please contact Katie Coleman at katie.coleman@tufts.edu.
The End of the Non-Proliferation Regime?
By Ian Johnstone, Professor of International Law
(June 25) Whatever short-term benefit is gained from setting back Iran’s nuclear program for a period is likely to be outweighed by a much greater long-term threat: the unravelling of the nuclear non-proliferation regime. In a worst-case scenario, Iran will withdraw from the Nuclear Non-Proliferation Treaty (NPT) and a domino effect will ensue. Saudi Arabia and other states in the region could follow suit. In South Korea and Japan, the discourse about going nuclear has already changed, due to North Korea’s acquisition of nuclear weapons and uncertainty about the US ‘umbrella.’ Even in Europe, France’s recent offer of nuclear protection may not be enough to prevent other European states from reconsidering their options.
Short of that worst-case scenario, if Iran is unshackled from the constraints of the NPT - and the reputational costs associated with violating it - other countries are likely to start hedging their nuclear bets. The non-proliferation regime is already fragile, having suffered a series of blows: North Korea’s withdrawal from the NPT, the demise of the JCPOA prompted by President Trump’s renunciation of it, the end of US-Russia arms control treaties, Russia’s nuclear threats against Ukraine and the failure of the last two NPT Review Conferences. Even if we don’t see a quick demise of the regime, its slow unraveling could accelerate.
Of course, it is possible that the strikes on Iran will deter others from seeking to go nuclear, as some have suggested. But that seems like wishful thinking in this geopolitical climate. Moreover, the perpetual threat of military action is an uncertain and highly volatile way of stemming the proliferation tide. A wiser approach is a full-throated diplomatic effort to shore up a regime that has been remarkably successful in keeping the number of nuclear states to nine, rather than the 25 feared by President John F. Kennedy before the NPT came into force.
Nuclear Weapons Strategy
By David C. Logan, Assistant Professor of Security Studies
(June 24) Recent U.S. strikes against elements of Iran’s nuclear program illustrate why such strikes sometimes occur and why they are often likely to fail.
Research indicates that states are more likely to attack nuclear programs when the target is a strategic rival, is non-democratic, is relatively weak militarily, and when the costs of strikes are seen as low. All of these factors are likely present in the U.S. strikes. Since 1979, Iran and the United States have been geopolitical rivals. Iran is a non-democratic. Prior to the strikes, Israeli officials claimed that they had eliminated most of Iran’s air defense systems, perhaps indicating to the administration that there fewer operational risks to the strikes. Congress appears unlikely to impose domestic political costs and U.S. officials appear less concerned with incurring international normative costs. The administration may also have assumed, based on past experience, that the strikes against nuclear facilities would not trigger a further escalation. In the final days of the first Trump administration, the United States killed Iranian General Qassem Soleimani and Iranian retaliation resulted in no casualties and did not escalate further.
The U.S. strikes may, at best, be a tactical success and a strategic failure by failing to meaningfully delay or disrupt Iran’s nuclear ambitions, especially relative to a diplomatic solution, though it is too early to tell.
Research shows that strikes against nuclear facilities are likely to succeed when the nuclear program is new and underdeveloped, depends on external support, features a small number of chokepoints known to the attacker, and is physically vulnerable to strikes. Perhaps only the last condition is fulfilled in the recent U.S. strikes, though even this remains unclear.
Iran possesses a relatively mature nuclear program, featuring multiple facilities which would need to be targeted, including deeply buried structures. Iran’s nuclear program also is largely self-sufficient, having already developed and installed hundreds of centrifuges and stockpiled highly enriched uranium.
There are already indications that the strikes were less successful than initially claimed. U.S. officials now report that one of the underground targets has damaged but not destroyed. The IAEA reports that Iran has a stockpile of more than 400 kg of highly enriched uranium, enough material for perhaps 10 nuclear warheads (though it would have to be further enriched to higher levels before weaponization). Iran also likely has amassed a store of centrifuges and related components. According to Israeli officials, Iran had moved equipment and uranium from its nuclear sites days before the strikes. Commercial satellite imagery reveals cargo trucks operating at least two facilities in the days before the strikes, possibly part of an effort to transfer nuclear equipment and material. U.S. officials now say they cannot account for this material. Iran may operate additional secret facilities with which it can reconstitute its program.
Just as importantly, any delays created by military strikes must be weighed against what might have been possible through a diplomatic solution. Officials claim that the strikes may have set back Iran’s nuclear program by “months, if not years.” The Iran nuclear deal would have limited elements of Iran’s nuclear program for 10 to 15 years. As multiple experts note, diplomacy is often held to higher standards than military strikes.
Professor Monica Duffy Toft's analysis is referenced in an article on how the U.S. strikes reflect themes in great power competition. (June 25)
Professor Monica Duffy Toft speaks to public radio program The World about how Israel, Iran and the United States can escape a cycle of escalation. (June 24)
Ambassador Donald Heflin, Executive Director of Fletcher's Edward R. Murrow Center, assessing the Iran-Israel ceasefire agreement in an interview with The Conversation. (June 24)
Professor Michael Glennon, former legal counsel for the Senate Foreign Relations Committee, speaks to NPR about congressional war powers. (June 23)
On CNBC's Access Middle East, Professor Monica Duffy Toft discusses Iran’s leadership future, Netanyahu’s resurgence, and the regional balance of power. (June 23)
In his regular opinion column for MSNBC, Senior fellow Michael A. Cohen assesses the Democrats' response to the U.S. strikes on Iran. (June 23)
Fletcher alumnus Vali Nasr appears on NPR's Morning Edition to analyze U.S. strikes and their impact on the Middle East. (June 23)
Professor Tom Dannembaum speaks to German news network Deutsche Welle about the legal frameworks governing Israeli attacks on Iran. (June 18)
Professor Tom Dannembaum appears on CNBC's The Exchange to discuss Israeli strikes on Iran and their status under international law. (June 16)