News on Jan. 13 that Iran has started work on an assembly line to manufacture uranium metal makes it more imperative to quickly restore the 2015 nuclear accord that restricted such activity, although Iran’s move may also make it harder for President-elect Joe Biden to follow through on his election pledge to resume US compliance with the deal, known as the Joint Comprehensive Plan of Action (JCPOA).

Laying out his plan in a Sept. 13 article via CNN, Biden said he would return the United States to the accord if Iran returned to strict compliance with its nuclear limits. He implied it would be a clean “compliance for compliance” trade-off. Biden did not insist that Iran would have to move first; the typical diplomatic solution is for simultaneous actions. Nor did he set other conditions. Biden said he would use a restored JCPOA as a basis for engaging Iran on other issues of concern, including Iran’s missile program, involvement in regional conflicts, detention of American citizens and human rights abuses.

Biden’s plan faces considerable opposition from those who insist he should not “squander the leverage” that his predecessor’s “maximum pressure” campaign supposedly built up. But did that policy truly create leverage? US withdrawal from the JCPOA in 2018 and the avalanche of sanctions subsequently imposed created economic distress for Iranian citizens but completely failed to achieve any of the 12 demands laid out by Secretary of State Mike Pompeo on May 21, 2018. To the contrary, Iran’s position hardened across the board. As former CIA Iran analyst Paul Pillar explained, leverage was destroyed, rather than accumulated, when the Trump administration punished Iran even though it was adhering to the JCPOA conditions. And having betrayed its partners, the United States is in a worse position than it was while negotiating the JCPOA. With the exception of a couple of states in the Middle East, all US partners want a clean return to the deal.

Meanwhile, Iran has been building up its own leverage over the past 18 months by steadily reducing its own commitment to the deal. By accumulating 12 times the amount of enriched uranium allowed by the deal, employing 174 advanced IR-2M centrifuges and increasing the enrichment level to near 20%, Iran has advanced its nuclear weapons potential to the point where, theoretically, it could produce a weapon’s worth of weapon’s grade uranium in less than three months.