Verification

Under the new approach, Iran permanently gives up none of its equipment, facilities or fissile product to achieve the proposed constraints. It only places them under temporary restriction and safeguard—amounting in many cases to a seal at the door of a depot or periodic visits by inspectors to declared sites. The physical magnitude of the effort is daunting. Is the International Atomic Energy Agency technically, and in terms of human resources, up to so complex and vast an assignment?

In a large country with multiple facilities and ample experience in nuclear concealment, violations will be inherently difficult to detect. Devising theoretical models of inspection is one thing. Enforcing compliance, week after week, despite competing international crises and domestic distractions, is another. Any report of a violation is likely to prompt debate over its significance—or even calls for new talks with Tehran to explore the issue. The experience of Iran’s work on a heavy-water reactor during the “interim agreement” period—when suspect activity was identified but played down in the interest of a positive negotiating atmosphere—is not encouraging.

Compounding the difficulty is the unlikelihood that breakout will be a clear-cut event. More likely it will occur, if it does, via the gradual accumulation of ambiguous evasions.

Advanced spying and monitoring technologies are most useful for figuring out whether Iran is cheating at secret, undeclared nuclear facilities. One tool the IAEA has access to is commercial, high-resolution satellite technology that can give them imagery of locations all across Iran.

“That capability has revolutionized the ability to find things that were once hidden in remote locations,” said Tom Shea, who worked at the IAEA for 24 years and helped establish nonproliferation safeguard procedures.

Satellites—like DigitalGlobe’s WorldView-3 orbiter—can be used to take photographs in the shortwave infrared spectra, for example, detecting a clandestine reactor that is putting off heat. Electro-optical and radar satellites could help complete the picture. (That’s one of the ways that the U.S was able to find Iran’s previously secret underground nuclear facility in 2009.

Another tool for finding clandestine sites is environmental sampling, which has improved to the point where inspectors can identify infinitesimally minute particles to find hidden nuclear facilities or sniff out misuse at declared facilities.

“You can detect individual atoms, very small samples, so it’s virtually impossible to hide that you’ve been doing nuclear activity in a room,” Persbo said.

And by using remote environmental technologies, the IAEA can engage in “wide area monitoring of ambient air and the ground… they can detect [nuclear activities] without going directly into certain areas,” said Daryl Kimball, executive director at the Arms Control Association.

What the IAEA actually needs is some preliminary evidence about where a secret nuclear facility might be lurking. The much-discussed but little-understood Additional Protocol was developed precisely for that purpose, and the JCPOA obliges Iran to accept it, first voluntarily and subsequently on a legally binding basis. But, the JCPOA goes beyond the Additional Protocol in two innovative and important ways.

First, IAEA monitoring will be extended to declared yellowcake (the precursor material to the feedstock for enrichment) and to declared centrifuge components. This measure will deter Iran from diverting this material and equipment to a secret program. Iran could, of course, try to acquire yellowcake or centrifuge components secretly instead — but doing so would create more opportunities for detection.

Second, the deal also creates a “Procurement Working Group” to oversee the import of all equipment and material that either is used or could be used for nuclear purposes. The intelligence communities of the United States and its friends spend considerable resources monitoring Iranian imports. If they discover that Iran has obtained any items that should have been declared but weren’t, they will have acquired clear evidence of secret nuclear activities in Iran. They could hand this evidence to the IAEA, which could conduct inspections to investigate further.

All in all, therefore, the JCPOA provides for some impressive verification provisions to guard against sneak-out. That said, no one should be under any illusions. Detecting small, undeclared centrifuge plants is difficult, and there is no guarantee of success. But, perfection is not the right metric against which to assess a nonproliferation agreement. The real question is whether sneak-out is more likely with a deal or without one. And here the answer is clear: Sneak-out would be much more likely without a deal, because the IAEA’s powers to detect clandestine facilities would be much more limited.

But what about secret facilities? The brute fact about unknown facilities is that we cannot know what we don’t know. No agreement can provide 100-percent confidence that Iran will not cheat at a secret facility. Indeed, no one can have 100-percent confidence today that Iran has not already built a nuclear bomb at a secret facility. What has prevented the Iranians from doing this so far has been Tehran’s judgment that such an undertaking would be discovered and that the United States would act decisively to deny them success. The keys to sustaining effective deterrence are (1) rigorous efforts by the intelligence agencies of the United States and its allies, and (2) a credible military capability to act if Iran dashes toward a bomb.

Since the agreement imposes the most intrusive verification and inspection regime ever negotiated, it will significantly add to the ability of intelligence officials to discover any prohibited activity and enhance the legitimacy of U.S. or other countries’ military actions to stop Iran from developing nuclear weapons should it violate its commitments. Nonetheless, as experts and so-called experts debate a 24-day delay for direct inspections of suspicious activity, or insufficient answers about Iran’s earlier nuclear pursuits, no one should miss the larger truth: 99 percent of the work to assure that any Iranian cheating is discovered will be done by U.S. intelligence agencies and those of allies. That was true before the agreement and will remain so after—even though the new inspections regime will provide some helpful information and observations that would otherwise be unavailable.