One Huge Difference Between The US And Japan

From Business Insider

Of course, a key reason Japan has so few working age citizens is its hostility to immigration, which -- despite whatever you think about the DREAM act -- has not been an issue here. That being said, in order for the US to realize the benefits of a younger population, it's imperative that immigrants actually become integrated and productive, and not remain second-class economically, with poor upward mobility. If that can't be achieved, the demographic difference is moot.