I've been playing Germany on historical but I can't get Japan to join Axis. They always make their Greater East-Asian Co-Prosperity Pact instead. Then Romania joins them instead of Axis when they turn fascist. It makes for a very unhistorical Germany game. Four times in a row they've done it. Am I doing anything wrong? I've tried taking the 'Befriending Japan' doctrine early on but that didn't do anything.