Klaus Iohannis, Romania’s president, and his wife Carmen Johannis arrive at Joint Base Andrews, Md., March 30, 2016. Iohannis, along with more than 20 other foreign leaders, arrived here for the 2016 Nuclear Security Summit held in Washington, D.C. The summit provides a forum for leaders to reinforce commitments to securing nuclear materials. (U.S. Air Force photo by Senior Airman Ryan J. Sonnier/RELEASED)