In a tiny, windowless meeting room high above the streets of Tokyo, Haruhiro Nakano starts to cry. The rail-thin, 54-year-old fund manager, who looks like a faded former J-pop star, has just shared his investing pitch, which sounds so deceptively simple you may not appreciate just how radical it is: Japanese workers, Nakano says, should invest for retirement using the capital markets rather than letting more than $8.6 trillion fester in bank accounts.