THEY CAN'T ISLAMIFY FAST ENOUGH:

As important as good economic policies are, they will not fix Europe's core problems, which are demographic, not economic. This was the point made in a speech to the European Parliament in November by none other than Pope Francis. As the pontiff put it, "In many quarters we encounter a general impression of weariness and aging, of a Europe which is now a 'grandmother,' no longer fertile and vibrant."

But wait, it gets worse: Grandma Europe is not merely growing old. She is also getting dotty. She is, as the pope sadly explained in an earlier speech to a conference of bishops, "weary with disorientation."

Some readers might regret the pope's use of language -- we love our grandmothers, weary with disorientation or not. But as my American Enterprise Institute colleague Nicholas Eberstadt shows in his research, the pope's analysis is fundamentally sound.

Start with age. According to the United States Census Bureau's International Database, nearly one in five Western Europeans was 65 years old or older in 2014. This is hard enough to endure, given the countries' early retirement ages and pay-as-you-go pension systems. But by 2030, this will have risen to one in four. If history is any guide, aging electorates will direct larger and larger portions of gross domestic product to retirement benefits -- and invest less in opportunity for future generations.

Next, look at fertility. According to the Organization for Economic Cooperation and Development, the last time the countries of the European Union were reproducing at replacement levels (that is, slightly more than two children per woman) was the mid-1970s. In 2014, the average number of children per woman was about 1.6. That's up a hair from the nadir in 2001, but has been falling again for more than half a decade. Imagine a world where many people have no sisters, brothers, cousins, aunts or uncles. That's where Europe is heading in the coming decades. On the bright side, at least there will be fewer Christmas presents to buy.

There are some exceptions. France has risen to exactly two children per woman in 2012, from 1.95 in 1980, an increase largely attributed to a system of government payments to parents, not a change in the culture of family life. Is there anything more dystopian than the notion that population decline can be slowed only when states bribe their citizens to reproduce?

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