Niebuhr's contributions to political philosophy include utilizing the resources of theology to argue for political realism. His work has also significantly influenced international relations theory, leading many scholars to move away from idealism and embrace realism. A large number of scholars, including political scientists, political historians, and theologians, have noted his influence on their thinking. Aside from academics, activists such as Myles Horton and Martin Luther King Jr. and numerous politicians have also cited his influence on their thought, including Hillary Clinton, Hubert Humphrey, Dean Acheson, James Comey, Madeleine Albright, and John McCain, as well as presidents Barack Obama and Jimmy Carter. Recent years have seen a renewed interest in Niebuhr's work, in part because of Obama's admiration. In 2017, PBS released a documentary on Niebuhr, titled "An American Conscience: The Reinhold Niebuhr Story".