Mark Fitzpatrick is an Associate Fellow at the International Institute for Strategic Studies. Until 2019, he was Executive Director of the IISS Americas office and head of the Non-Proliferation and Nuclear Policy Programme. Before IISS, he had a 26-year career in the US Department of State, including as Deputy Assistant Secretary for Non-Proliferation (acting). He has produced ten books relating to proliferation, including as co-author of "Uncertain Future: The JCPOA and Iran’s nuclear and missile programmes (2019). On Twitter: @MarkTFitz