Who's going to pay for all this stuff?

I've written about P.D. James' creepy, dystopian novel "The Children of Men" before and Ross Douthat has a good article today about the unsettling demographic trends facing Japan in "The Incredible Shrinking Country."

Eberstadt has spent years writing about the challenges posed by declining fertility around the globe. But Japan, he notes, is a unique case. The Japanese birthrate hovers around just 1.3 children per woman, far below the level required to maintain a stable population. Thanks to increasing life expectancy, by 2040 “there could almost be one centenarian on hand to welcome each Japanese newborn.” Over the same period, the overall Japanese population is likely to decline by 20 percent, with grim consequences for an already-stagnant economy and an already-strained safety net.

Yikes, one centenarian per baby?  That's going to lead to some budget strains unless Japan can get some kids into the work force.