LOL...you don't know much about Japan, do you? Japan's population is shrinking. Japan - total population 2012-2022 | Statistic That is an absolute disaster for long term GDP growth...especially so for a nation that is aging fast. Plus, Japan has BY FAR the highest debt to GDP ratio in the world. http://worldpopulationreview.com/countries/countries-by-national-debt/ Japan is in deep shit...unless they get their women to pop out a LOT more babies, they will have no choice but to abandon their xenophobic nonsense or their country will eventually collapse. So much for your example of Japan doing well by remaining 'pure'. We are done here. Have a nice day.