This report reflects what happened during a three-move diplomatic simulation NPEC hosted in August 2021 and in the game's three preparatory meetings. The simulation was set in the present day (summer 2021). Participants responded to a scenario in which Iran threatened to withdraw from the NPT, after which Israel released photos of Iran secretly manufacturing implosion devices. Participants assumed the roles of members of the U.S. National Security Council, key foreign officials, and members of the United Nations Security Council. In the first move, the U.S. President, responding to the crisis, called a National Security Council Principals Committee meeting to draft a U.S. resolution to the U.N. The U.S. Ambassador to the U.N. presented this resolution during a mock U.N. Security Council meeting in the second move. The resolution did not pass. In the third move, participants debated what strategies might ensure the future viability of the NPT and prevent Iran from breaking out and making a bomb.