https://www.christianitytoday.com/ct/2017/may-web-only/theology-of-james-comey-fbi-niebuhr-trump.html

How did this particular theologian become so many politicians’ moral and spiritual compass? Niebuhr developed a view known as Christian realism, believing the human ego would undercut our attempts to better the world. According to Niebuhr, people need to shed their self-righteous illusions and perfectionist pretensions to set their sights on more modest solutions. Niebuhr warned that people should never assume they could eliminate evil. In fact, they should be on guard lest their moral ambitions lead them into a self-deluded and destructive pride.