Before he became editor of Breitbart, Bannon made many propaganda films. He also was behind the book the book Clinton Cash. Clinton Cash was full of innuendos and statements accusing the Clintons of things that he later admitted the author could not back up. It was partially reprinted in the New York Times and was one of the things that was used to smear Hillary. Bannon is so good at propaganda that Peter Schweiazer of the Hoover Institution, a powerful right-wing think tank, called him “the Leni Riefenstahl” of the Tea Party. Leni Riefenstahl made a propaganda film for Hitler called Triumph des Willens (“Triumph of the Will”) which is considered to be the best and most successful propaganda film in history. It is still studied and elements of it are used in advertising to this day.
What this means is that even though T*mp might be a loose cannon, Bannon is an experienced expert at propaganda and everything that is happening is based on his agenda. He knows exactly what he is doing, he has many decades of experience, and he is the best in the business.