Analysis & Opinions - Belfer Center for Science and International Affairs, Harvard Kennedy School

Commentary on “The Iran Nuclear Archive: Impressions and Implications”

A group of experienced and respected nuclear experts from Harvard Kennedy School’s Belfer Center for Science and International Affairs travelled earlier this year to Israel to examine the trove of documents on Iran’s nuclear program that had been obtained via a clandestine operation. They recently published their assessment of that material in the report The Iran Nuclear Archive: Impressions and Implications, which provides a valuable fact check on claims that were made when the archive was first revealed a year ago by Israeli Prime Minister Benjamin Netanyahu. Although the authors of the Belfer Center report chose not to promote a policy conclusion, we believe a policy conclusion is in fact warranted by their review: The Joint Comprehensive Plan of Action (JCPOA) is needed both to ensure continuing thorough international verification of Iran’s nuclear activities, including any new information on the specifics of past Iranian nuclear weapons activities, and, vitally, to provide the tools to dissuade Iran from resuming a clandestine program that could provide weapons-usable fissile material.

The archive confirms the well-known fact that Iran had a “structured program” for nuclear weapons development through 2003, with some additional activities continuing for several years thereafter. Obviously, this was clearly understood by the Obama Administration and informed the pursuit of an international agreement to stop Iran’s march to the bomb by curbing fissile material production, the essential ingredients of a nuclear weapon. The detailed negotiations led by the United States resulted in the conclusion of the JCPOA in the summer of 2015.

The emphasis on fissile materials in the JCPOA is manifest through its significant restrictions on Iranian nuclear activity for fifteen years, and specifically a minimum “breakout time” of one year for at least ten years. The breakout time is defined as the time required to accumulate a bomb’s worth of nuclear weapons material even in the easily detected case of an all-out sprint to the bomb. When calculating the breakout timeline, no credit is taken for the additional effort needed to make a nuclear weapon – and the archive shows the wisdom of the negotiating focus on fissile materials accumulation.

While the authors make much of what intelligence collection did not detect, such as the Iranian intent to use a known tunnel for uranium activities before any relevant equipment was installed, their overall conclusion about fissile material production validates the explicit knowledge upon which the U.S. and its negotiating partners based the effort to secure the agreement: “At the same time, the combination of national intelligence activities and IAEA efforts had successfully identified that Iran had a program focused on development of nuclear weapons and had successfully uncovered nearly all of its efforts related to production of fissile material.”

The archive also points to various specifics of Iranian progress toward, and commitment to, nuclear weapons production, such as explosive design and weaponization, beyond what had been declared by the IAEA and various intelligence agencies. This leads to the conclusion that there are some answers worth pursuing about previous Iranian activities, even though the JCPOA negotiating context would not have changed as a result.

Indeed the requirements of various unique commitments that Iran was required to make in the JCPOA, such as a permanent ban on various weaponization activities (Section T), derived directly from the negotiators’ intimate understanding of the Iranian nuclear weapons program. The core negotiating focus was always on the production of nuclear weapons-usable fissionable material production and on establishing an unprecedented verification regime to address not only declared Iranian peaceful nuclear activity but also the possible clandestine activity that was and would surely be Tehran’s route to nuclear weapons.

The most important feature of the JCPOA is precisely this unique transparency and verification regime. Under conditions of continuing implementation, the agreement assumed that any resumption of Iranian nuclear weapons activity would again be clandestine—and it therefore included specific agreed provisions to address cheating. For this reason, the JCPOA requirement for Iran to follow the Additional Protocol and, unlike any other country, to permanently allow IAEA access to suspect sites in no more than twenty-four days is crucial. The importance of access in a relatively short time should be obvious and is reinforced by the Belfer Center report’s statement that Iran avoided the use of uranium in various tests out of a concern that uranium contamination of facilities could be detected.

If the Trump Administration finally drives Iran to withdraw from the JCPOA, the most critical tools available to detect nuclear weapons activity will be lost. Former Director of National Intelligence Jim Clapper said upon signature of the JCPOA that, while no specific clandestine activity can be detected with 100 percent confidence, the agreement considerably raised the bar for Iran to avoid detection. This is important in the context of the United States and others having detected pre-JCPOA Iranian efforts for uranium enrichment even before the addition of the new and greatly enhanced monitoring tools enshrined in the deal. Further, the negotiating cohesion evidenced by the E3/EU+3, even in the midst of difficult relations between Russia and the West due to Russia’s assaults on Ukrainian sovereignty, made clear to Iran that it would face comprehensive international isolation for violating the JCPOA. Now, perversely, the U.S. Administration has diminished the likelihood of a cohesive global approach should Iran follow the U.S. in leaving the JCPOA.

President Trump’s decision to unilaterally pull out of the agreement is fundamentally contrary to the national security interests of the United States and its allies and partners—and to the stability and security of the planet. Any serious plan to prevent Iran from acquiring a nuclear weapon must begin by paving a path back to the JCPOA’s fundamental principles of limiting breakout time coupled with an unparalleled verification regime that does not sunset.


The authors served as Secretary and Deputy Secretary of Energy respectively in the second term of the Obama Administration, and both are nonresident senior fellows of the Belfer Center. Secretary Moniz was a principal negotiator of the JCPOA.

For more information on this publication: Belfer Communications Office
For Academic Citation: Moniz, Ernest and Elizabeth D. Sherwood-Randall.“Commentary on “The Iran Nuclear Archive: Impressions and Implications”.” Belfer Center for Science and International Affairs, Harvard Kennedy School, May 13, 2019.