The ongoing Israeli bombings of Iranian nuclear facilities and Tehran’s threats to develop a nuclear weapon clearly indicate that the nonproliferation regime is entering a more volatile phase. Iran’s threats to withdraw from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) will cause tremendous strain on future diplomatic efforts to prevent the spread of nuclear weapons. Since 1970, the NPT has been the bedrock of the nuclear order, promoting nonproliferation through its normative and legal power. Analysts have frequently noted that the power of the NPT is waning, and the ongoing conflict will only expedite this erosion. However, the nonproliferation tool kit comprises much more than a single treaty, and the enforcement of this regime has always been supported by hard power. In today’s increasingly competitive security environment, states appear to be more willing to employ military force to achieve their objectives. This is not the first time that the nonproliferation regime has been challenged. The year 2003 presented multiple obstacles for nonproliferation. In January of that year, North Korea announced its intent to withdraw from NPT, sending an undeniable signal to the world that then–Supreme Leader Kim Jong-il intended to build a nuclear weapons program. March witnessed a U.S.-led coalition invade Iraq to eliminate its alleged weapons of mass destruction (WMD) program. In June, the International Atomic Energy Agency issued a report on clandestine nuclear activities in Iran, assessing that Tehran was studying how to weaponize nuclear technology. By October, U.S. intelligence agencies had seized uranium centrifuge equipment bound for Libya as part of Libyan leader Muammar Gaddafi’s clandestine nuclear weapons program. The Israel-Iran conflict today represents a return to military force to resolve nonproliferation compliance concerns. This conflict holds three key implications for the nonproliferation regime: First, proliferation risks will rise. Second, military counterproliferation efforts will be increasingly relevant as a tool to prevent the spread of nuclear weapons. Third, despite a growing isolationist foreign policy, the United States is willing to consider military intervention to pursue vital nonproliferation objectives. Proliferation Risks Are Rising In a world characterized by great power competition and geopolitical instability, the security benefits provided by nuclear deterrence are increasingly alluring. This dynamic was present in the international system prior to the Israeli attacks on Iran’s nuclear facilities. For example, in 2024, just before taking office, Japanese Prime Minister Shigeru Ishiba called for an Asian version of NATO, which could include introducing nuclear weapons to the region. Similarly, in 2023, then–South Korean President Yoon Suk Yeol stated, “It’s possible that the problem gets worse and our country will introduce tactical nuclear weapons or build them on our own,” reflecting a growing debate in Seoul about its nuclear options in the face of persistent threats from Pyongyang. In the Middle East, Saudi Arabia is currently pursuing an agreement with the United States to develop nuclear energy capabilities. While ostensibly for civilian nuclear power, those same capabilities could be leveraged as part of a nuclear latency strategy. Particularly concerning capabilities that may be included in a future deal between Washington and Riyadh are uranium enrichment and plutonium reprocessing. If Saudi Arabia develops domestic enrichment or reprocessing technologies, the country would have the key components required to develop nuclear weapons if regional security dynamics demand it. Iran’s failed attempts at proliferation reveal a key lesson for future would-be proliferators. For over a decade, Tehran has employed an overt nuclear hedging strategy, developing latent capabilities while simultaneously playing a political game of brinksmanship about its nuclear future. For example, in 2022, Iran’s atomic energy chief stated that Iran possessed the ability to build a bomb but was not pursuing weaponization. Similarly, in 2024, a senior adviser to Supreme Leader Ayatollah Ali Khamenei claimed that Iran had made “no decision to build a nuclear bomb, but should Iran’s existence be threatened, there will be no choice but to change our [Iran’s] military doctrine.” The past few weeks have illustrated that prolonged periods of nuclear hedging, employed as a deliberate strategy, create significant international pressure to prevent proliferation. In the future, proliferators may seek to develop latent nuclear capabilities. However, pursuing nuclear hedging as a deliberate and overt strategy seems less likely to be successful. Future proliferators will probably attempt to develop a bomb more quickly or keep their political intentions more opaque. Counterproliferation Is Increasingly Important For the past two decades, the international community has largely resolved proliferation concerns through the pursuit of diplomatic options. Between 2010 and 2016, the world sought to reduce terrorist and nonstate actor nuclear threats through the Nuclear Security Summits. Syria’s chemical weapons were destroyed through the Syrian peace process. In 2015, the Obama administration negotiated the now-defunct Joint Comprehensive Plan of Action (JCPOA) with Iran. In 2018, the Trump administration sought to constrain North Korea’s nuclear programs through a series of largely ineffective summits. Multilateral diplomacy and communiques appear to be playing a less prominent role in the current environment. Israel’s pursuit of military counterproliferation options to destroy the Iranian nuclear program marks a pendulum shift back to the use of hard power by powerful states to constrain the spread of WMDs. The efficacy of such counterproliferation efforts to constrain the development of nuclear weapons is hotly debated. Some analysts argue that military attacks on nuclear facilities only drive nuclear weapons programs more underground while simultaneously galvanizing domestic political will to develop a nuclear deterrent. Others believe that military options are preferable to negotiating convoluted arms control agreements with countries that have a history of acting in bad faith. Reports suggest that Mossad, the Israeli intelligence agency, has penetrated deep into Iranian territory, utilizing advanced tactics such as drones and high-precision missiles to target Iranian surface-to-air missile launchers and other critical infrastructure. The Israel Defense Forces have even claimed to have destroyed up to a third of Iran’s missile launchers, greatly reducing Iran’s ability to launch large ballistic missile salvos. Israel’s actions against the Iranian nuclear program, often conducted covertly, have demonstrated its ability to cripple key components of a rival’s nuclear infrastructure. Such successes highlight the critical role that actionable intelligence and the ability to penetrate the security apparatus of target states play in successful counterproliferation efforts. U.S. Isolationism Has Limits The Trump administration has made “America First” a priority that is driving nearly all aspects of U.S. domestic and foreign policy. Political leadership in the Trump administration has pursued greater isolationism with regard to U.S. economic, military, and political commitments abroad. Many things are shifting in U.S. foreign policy, but the Trump administration’s rhetoric and support of Israeli actions in Iran may illustrate that the United States remains committed to the nonproliferation mission. Recent scholarship on U.S. grand strategy has emphasized nonproliferation as a guiding principle of foreign policy since the first atomic bombs were dropped in 1945. The United States has consistently pursued nonproliferation goals, even, at times, when it required working with enemies, working against allies, and working with proliferators to contain their proliferation violations. During the Cold War, the United States worked with the Soviet Union to prevent the spread of nuclear weapons. U.S. nonproliferation policy simultaneously sought to prevent allied proliferation. The United States threatened Israel with abandonment and sanctioned Pakistan, South Africa, and India for weaponization activities. Under the Ford and Reagan administrations, the United States warned of troop withdrawal and sanctions if the Republic of Korea did not halt nuclear weapons research. Additionally, U.S. threats of military abandonment appear to have played a key role in West Germany’s cessation of nuclear weapons activities. In order to accomplish its nonproliferation mission, the United States has leveraged a wide variety of tools, including multilateral instruments, U.S. defense and security agreements, and counterproliferation efforts. Despite its stated aversion to foreign entanglements and a clear desire to extricate the United States from costly overseas conflicts, the Trump administration reportedly is considering military options against Iranian nuclear facilities. Public statements from high-ranking officials frequently hint at, or outright discuss, the potential for strikes to prevent Iran from acquiring a nuclear weapon. This contemplation of kinetic action stands in stark contrast to the administration’s broader America First doctrine, which prioritizes domestic issues, seeks to reduce the U.S. overseas military footprint, and often views military interventions with skepticism. In the past, diplomatic options have often prevailed to resolve nonproliferation concerns despite the consideration of other military options. Whether diplomacy is successful this time in Iran may depend on whether Tehran is willing to give up every aspect of its nuclear program, including all enrichment capabilities, despite the ongoing conflict. As many foreign policy priorities are changing, President Trump’s comments and actions on the Iran conflict have indicated that nonproliferation remains a vital national security objective. The administration has repeatedly emphasized that Trump wants a nuclear deal with Iran despite the U.S. withdrawal from the JCPOA in 2018, during Trump’s first term. This desire is underscored by a fundamental bipartisan consensus that the spread of nuclear weapons poses an unacceptable risk to global stability. Conclusion The nonproliferation regime has long relied on relied upon norms, rules, and international legal structures to constrain the spread of nuclear weapons. The potential withdrawal of Iran from the NPT, following the precedent set by North Korea, threatens to accelerate a shift toward a more confrontational and less legally bound geopolitical environment. In this new landscape, states willing to use force, or the threat of it, to prevent proliferation may increasingly hold the cards. This does not mean the end of nonproliferation efforts, but it does mark a dangerous transformation in their character and efficacy. The international community must adapt to this reality, pursuing robust diplomatic efforts to uphold the NPT where possible, while also recognizing and preparing for a future where deterrence and direct counterproliferation actions may play an even more prominent role. Joseph Rodgers is the deputy director of the Project on Nuclear Issues and a fellow in the Defense and Security Department at the Center for Strategic and International Studies in Washington, D.C.