President Trump is widely expected to “decertify” the Iran nuclear deal this week. According to press reports, he will contend that continuing with the deal is not in the national security interests of the United States (despite his top generals explicitely stating otherwise). He will then pass the buck to congress, which will have to decide whether or not to re-impose sanctions.
But for the purposes of the Joint Comprehensive Plan of Action (JCPOA) — the name of the Iran nuclear deal — this move is both formally irrelevant and diplomatically very awkward. The JCPOA is not an agreement between the United States and Iran. It is an agreement between the UN Security Council, of which the US is a member, and Iran. To be sure, the United States was the key negotiator and instigator of this deal. But it was enshrined by a vote of the Security Council in June 2015.
Resolution 2231 was passed unanimously by the Security Council. It specifically endorses the deal and calls on all parties to abide by its strictures. There is no provision in the JCPOA or Resolution 2231 that allows a party to unilaterally walk away from the deal by the stroke of a pen of the US President.
While Trump’s non-certification has no formal implications for the Iran Deal, it nonetheless puts the United States in a very awkward position.
The United States president would be signaling to the world that it does not support a key UN Security Council resolution for which the United States voted just two years ago. And if Congress approves a re-imposition of sanctions, the United States could find itself in violation of its own Security Council resolution. In the near term, this could dissolve the Iran Nuclear Deal and lead to the proliferation of nuclear weapons in the world’s most volatile region. In the long term, the undermining of a Security Council resolution by a member of the Security Council reduces the overall utility of the Security Council as a forum to addressing global threats.
This includes North Korea, where the Trump administration has made Security Council sanctions the centerpiece of its diplomatic efforts to confront Pyongyang. If the US undermines it’s own resolution on Iran, China may read from that playbook and walk back its commitments to previously imposed sanctions resolutions on North Korea. At that point, the one international forum designed to pressure North Korea on its nuclear program would no longer have any sort of meaningful effect.