In 2010 27.4% of the US population was under the age of 20; the Frankfurter Allgemeine Zeitung reported on August 3 that only 16.5% of the population of Germany is under the age of 18. That's a staggering difference which demonstrates once again how difficult it is to establish permanent economic guarantees in any society. Particularly in the American system, in which we never actually have cash in a program like Social Security but simply pay current retirement benefits with the cash coming in from workers' salaries at the moment, we require enough workers at any given time to pay for the retirees currently receiving benefits. Without setting up individual accounts, in which my money, which I pay into the system, remains untouched by anyone else and unused until I retire, the entire system is at the mercy of demographics. I.e., the fewer babies we have, the more expensive a program like Social Security gradually becomes. In a socialized system, everything depends on demographics, which makes it doubly odd that the left is generally for expanded social programs and smaller population growth. These two principles are completely inconsistent.
The fact that our future economic health also relies on the number of babies we have reminds us that social engineering can never insulate us from simple biology. Nature will always win out in the end. While we can insulate ourselves from it to some degree by air-conditioning, heating, artificial light, antibiotics, and shark nets at the beach, we cannot ultimately engineer the untouchable, self-sustaining economic safety net, a perfect machine that we can wind up and then leave to run smoothly while we amuse ourselves with other matters. Just as our very fine Consitutional republic also requires the cultivation of sacrificial virtue in order to function properly, so also our economic safety net demands the sometimes difficult sacrifices of having children in order to ensure a more secure future for the nation and the individuals in it.