And since it is the Muslim nations of North Africa and the Middle East that are closest to Europe, with easiest access to the continent, Muslims will likely furnish most of the multitudes who are coming.
What will this mean for Europe? Religious and racial conflict.
On Sept. 11, 2001, after the twin towers fell and Germany expressed her anguish and solidarity with America, a strange event occurred. In the Turkish districts of Berlin, bottle rockets were fired all night in celebration.
In the banlieues around Paris and other French cities, Arab riots, assaults on police and mass arson of vehicles regularly occur. This summer in London, the immigrant enclaves exploded and poured out into the city night after night.
Angela Merkel of Germany, seconded by David Cameron of Britain and Nicolas Sarkozy of France, declared multiculturalism had "utterly failed."
What is the future of Europe? What is the future of Western man? Houari Boumedienne, Algerian revolutionary and president of his country, predicted it at the United Nations in 1975.
"One day, millions of men will leave the Southern Hemisphere of this planet to burst into the Northern one. But not as friends. Because they will come in to conquer, and they will conquer by populating it with their children. Victory will come to us from the wombs of our women."
Boumedienne's words were spoken just as European and Western birth rates plunged below ZPG.
What, then, is the future?
A Russia with not one-tenth China's population will not hold on to a continental nation twice China's size. Already the Russian Far East is being invaded by Chinese crossing the Amur and Ussuri rivers to work, even as Mexicans cross the Rio Grande to reoccupy lands torn away from their ancestors in 1836 and 1848.
What is the future of the West?
China will retrieve all the lands lost to Russia in the 19th century and slices of Russia that China never owned. Mexicans and Hispanics will dominate from the Floridas to the American Southwest the lands Spain and Mexico lost to the United States in the 19th century.
Africans, whose lands were colonized and exploited by Europeans, and Muslims and Arabs, whose ancestors were turned back at Poitiers and Vienna, will succeed in the final conquest of Europe.
Demography is destiny.