There's a critical unknown emerging in the Iran deal

One of the big unanswered questions in the wake of the historic nuclear deal between a US-led group of countries and Iran had to do with the status of a side-agreement reached between the International Atomic Energy Agency and Tehran.

On July 14th, hours before the nuclear agreement was officially announced, Iran and the IAEA signed a "roadmap" agreement on the disclosure of Iran's prior nuclear weaponization activities.

The IAEA and Iran have been wrangling over Iranian cooperation with IAEA investigations into its weapons program for nearly a decade.

After years of difficulty, the roadmap gives the IAEA until October to investigate the extent of Iran's weaponization work and until December to issue a final report on their findings.

But it's unclear exactly what happens if Iran doesn't comply with the investigation, or if the IAEA reports that Tehran has been generally uncooperative in disclosing the past or current extent of their program.

And it's far from obvious what's even required of Iran under the roadmap, or what happens if the IAEA's vague criteria aren't met.

"There are no explicit requirements that Iran must cooperate sufficiently so that the IAEA can report that its concerns are addressed,"an analysis by the Institute for Science and International Security notes.

"If Iran provides by August 15 unsatisfactory answers about its past nuclear work related to nuclear weaponization and the development of a missile payload for a nuclear weapon, what happens?"

The answer: possibly nothing.

On July 27th, the Wall Street Journal published a report on the Obama administration's briefing of lawmakers on the various non-public side-agreements reached between the IAEA and Iran on the implementation of the roadmap. According to the Journal, some of the administration material on implementation is actually classified.

As the Journal reports, the administration provided documents to lawmakers, concluding that an "Iranian admission of its past nuclear weapons program is unlikely and is not necessary for purposes of verifying? commitments going forward."

This language hints at a subtle compromise: Iran could reveal weaponizaton work without explicitly acknowledging its purpose, a "what, not why" approach that would provide valuable information to inspectors without forcing Tehran to admit to activity that's clearly illegal under the nuclear Non-Proliferation Treaty.

The administration documents the Journal quotes also suggest that the US is comfortable that it already knows the former extent of Iran's program: "The United States has shared with the IAEA the relevant information, and crafted specific ?measures that will enable inspectors to establish confidence that previously reported Iranian [weaponization] activities are not ongoing," the administration report states.

It appears the administration might believe it can help establish an IAEA inspection baseline for Iran's nuclear program - knowledge of illicit supply chains, expertise, undisclosed locations, and military oversight of nuclear technology - without Iran having to fully comply with the roadmap.

This is a bit of a gamble, and the Journal notes that former CIA director Michael Hayden recently told a Congressional committee that the US "[does] not have total knowledge of how much progress the Iranians had made."

Even analysts generally supportive of the deal have acknowledged that the weaponization disclosure issue was settled on favorable terms for Tehran. The International Atomic Energy Agency was "using Iranian language" in framing how disclosure issues will be settled, as the Royal United Services Institute's Aaron Stein put it in an interview with Vox.

In a conference call with reporters a few days after the deal was announced, Carnegie Endowment for International Peace nonproliferation expert George Perkovich, who has a generally positive view of the deal, speculated that "you're never going to have many of these questions fully resolved."

As Perkovich put it, the IAEA will determine that it "can't make a final pronouncement on X, on Y, and on Z," and the agreement would have to move forward in spite of that.

But there's an even more basic problem: The sides seem to disagree on the relationship between the IAEA roadmap and the other, much larger nuclear deal between the US and its partners.

As the Journal report notes, Ali Akbar Sahelhi, the head of Iran's atomic energy agency, recently stated that "the IAEA's investigation was independent of the broader deal."

At the same time, "US and IAEA officials have said ... that sanctions on Tehran won't be lifted if the country doesn't cooperate in the probe."

So Iran and the rest of the international community don't seem to agree on whether Iranian stalling on military disclosures should have any impact on how and whether the other nuclear deal is implemented.

Whatever the extent of Iran's cooperation with the IAEA - and whatever details of the roadmap's implementation remain hidden from public view - it's this differing interpretation of what the nuclear deal actually requires that could be the most significant early indicator of the agreement's viability.

Within a few weeks of the deal's announcement, there's already a substantive disagreement on what the accord actually obligates the two sides to do, and how one very important part of the Iranian nuclear issue relates to the broader whole.