Hillary Clinton, former U.S. secretary of state and 2016 Democratic presidential candidate, testifies during a House Select Committee on Benghazi hearing in Washington, D.C., U.S., on Thursday, Oct. 22, 2015. Under scrutiny for her handling of the Benghazi attacks and her use of a private e-mail server, Clinton plans to invoke the memory of slain U.S. ambassador Christopher Stevens to defend her approach to diplomacy, saying they shared a common belief in the need for America to lead. Photographer: Andrew Harrer/Bloomberg via Getty Images