On Oct. 31, the U.N. Population Fund marks the arrival of the 7 billionth person on Earth and raises the population estimate for the planet at mid-century to 9.3 billion people. There is a possibility, says the United Nations, that, by century's end, world population may reach 15 billion. What does this mean for Western civilization? It may not matter, except to identify who inherits the estate. For while world population is exploding, Western peoples are dying. Not a single European nation, except Muslim Albania, has a birth rate that will enable it to replace its present population. By mid-century,...