Left-wing fascism (or left fascism) is a term for left-wing politics that resemble fascism in some way. However, fascism is widely known as a form of far-right politics. The concept was first written about shortly after World War II, by researchers such as Jürgen Habermas, Irving Louis Horowitz, and Victor Klemperer. They criticised specific left-wing groups that they thought were becoming more fascistic.