The argument for the Iran nuclear deal was always that it was better than the status quo. We got inspectors into Iran and we had a much better idea what the Iranian government was doing. By all indications, Iran was complying with the deal. After Trump backed out and began applying “maximum pressure,” Iran quit complying with the terms of the deal. The US’s has hypocritically insisted that Iran comply with a deal the US backed out of, and now the Biden administration is insisting that Iran renegotiate a more stringent deal. Iran has not buckled under US sanctions, nor will it negotiate a more stringent deal. It might not even accept the original deal. From Paul R. Pillar at responsiblestatecraft.org:
Insofar as U.S. policy influences Iranian policy, those who have always opposed the Joint Comprehensive Plan of Action, the multilateral agreement that limited Iran’s nuclear program, have to be creative in constructing their talking points. The record of the last six years has shown that the first half of that period, when the JCPOA was fully in force and international monitoring confirmed Iran’s compliance with the strict limits that the agreement had imposed on Iran’s nuclear activities, was markedly better than the second half that began after the Trump administration reneged in 2018 on U.S. obligations under the JCPOA and thereby relieved Iran of its obligations.
Trump’s subsequent “maximum pressure” campaign against Iran was a conspicuous failure on every front. A year after Washington’s reneging, Iran started ramping up its uranium enrichment beyond the JCPOA limits to the point where the estimated “break-out” time it would now need to make enough fissile material for a nuclear weapon is down to only a month or two, rather than approximately a year under the JCPOA. Iranian regional activity became at least as aggressive as it was before. And with the U.S. reneging having politically discredited those leaders within Iran who favored concessions and negotiations with the West, hard-liners are now firmly in control in Tehran.
Among the creative arguments attempted by JCPOA opponents is to blame the consequences of withdrawal that have flowed on the JCPOA itself, instead of on Trump’s renunciation of the deal. Richard Goldberg of the misleadingly named Foundation for Defense of Democracies, an advocacy group that has made opposition to diplomacy with Iran and especially the JCPOA its signature issue, tried this technique when I appeared with him several weeks ago in a program aired in Arabic to audiences in the Middle East. The current worry about breakout times is due to shortcomings of the JCPOA, argued Goldberg, because it left Iran with a nuclear base from which it could expand. He left unsaid that the base Iran had before it was required to dispose of most of it under the JCPOA was many times bigger than what it had when the agreement was in force.