Four of world's biggest countries could 'collapse' as 'era of depopulation' takes hold
![Four of world's biggest countries could 'collapse' as 'era of depopulation' takes hold](https://i2-prod.dailystar.co.uk/incoming/article32793521.ece/ALTERNATES/s615/0_People-Visit-Osaka-After-May-Day-Holiday.jpg)
Population decreases in East Asia have seen a potential 'collapse' on the cards for Japan and China as their depopulation means the United States will surpass them as a world power by 2050