President Joe Biden refused to commit to keeping sanctions lifted on Iran for the rest of his term, even if Iran rejoins and complies with the nuclear deal.

EU diplomats recognize that the ease with which the United States can quit the agreement is a “serious and legitimate concern.” Tehran fears that the unreliability of the U.S. commitment to the JCPOA puts Iran in a very vulnerable position. By realigning with the JCPOA, Tehran will give up much of its nuclear leverage while Washington ostensibly lifts sanctions. However, sanctions relief will not lead to meaningful economic benefits for Iran unless Western companies feel confident about Washington’s longer-term fidelity to the agreement — which they do not. This would leave Iran giving up its leverage for nothing — particularly if Washington once again exits the deal.