I don’t think the majority of the human species has learned well the lessons of World War II. The fundamental lessons of World War II is that humanity has the willingness and the capability to destroy itself. In other words, humanity can, and without the required maturity will, cause it’s own extinction. The United States emphatically demonstrated this in dropping nuclear bombs on Japan. For most of my life we have lived in the fear of this knowledge, aka the fear of nuclear war, but we have not really learned the lessons about how we need to change. Wars and weapons of war are rooted in fear. The only way to overcome this fear is to be satisfied with enough and see others as a part of ourselves.