While Japan is not a party to the Joint Comprehensive Plan of Action (JCPOA), popularly known as “the Iran nuclear deal,” it played an important role in the conclusion of this international agreement and could be influential in its implementation. The global sanctions regime that helped drive Iran to the negotiating table depended upon the participation of major economic players like Japan. In concert with its U.S. ally and the rest of the international community, Japan endured economic costs in pursuit of shared nuclear nonproliferation principles and broader national interests. The JCPOA is an underappreciated example of cooperation between the United States and Japan on this front.

However, as the one-year anniversary of the JCPOA approaches in July, U.S. and Japanese interests are showing signs of divergence. Japan is expanding investment in Iran’s energy sector while the United States remains at odds with Iran over non-nuclear issues. How will Japan’s deepening economic partnership with Iran impact international nonproliferation efforts and the U.S.-Japan Alliance?...

Read the full article at the Diplomat.