India, Oct. 18 -- For too long, the West spoke of the rise of China as threat to international stability. Those statesmen got it backwards. It is the fall of China that creates the most danger

Historically, countries with burgeoning populations covet space and their neighbours' resources. Nazi Germany sought Lebensraum-living space-in Russia and Ukraine. Imperial Japan justified its invasion of Manchuria in similar fashion. More recently, Iraq sought to annex Kuwait.

Often, however, population decline can lead to aggression. Russia's population peaked around 148 million in the early 1990s but then fell for much of the following two decades largely due to low birthrates, high male mortality, and emigration; today, Russia's population is ...