FILE - In this Monday, March 9, 2009 file photo, The Harry S. Truman Building, headquarters for the State Department, is seen in Washington. The State Department has ordered non-essential diplomats at the U.S. Embassy in Chad to leave the African nation due to potential insurgent attacks on the capital, Saturday, April 17, 2021. The department said in a travel alert issued Saturday that it had taken the step because armed groups from the northern part of the country have moved south and appear headed toward the city.(AP Photo/J. Scott Applewhite, File)