Now, I made this argument earlier as part of another subject entirely, but I'm going to go into it further here.
One of the very interesting contradictions I find among some of the left is the tendency to browbeat and criticize myself and my wife for our "irresponsibility" in having a large family (five kids), while there are pockets of the planet that are overpopulated (and my having fewer kids is going to help India's overpopulation problem...HOW?!?). The contradiction comes from the fact that invariably, these individuals are against the move to privatize social security and wish to leave it as it is, where the current generation of workers pays for the last generation's retirement, rather than that generation's earnings going to fund their OWN retirement.
EXCUSE ME?
What you are saying, in essence, is that you want to maintain a system that pays your retirement from MY children's wages. Interesting.
Because you chose not to have children, that effectively makes you a mooch on the system. You didn't contribute to the labor pool that would provide for your retirement (and sorry, you can't count the money YOU paid to Social Security; remember, you fought AGAINST it being used for your own retirement). On top of that, you belittled and ridiculed those that DID have children. So, the morally "right" thing to do would be for you to refuse social security once you're old enough.
But I'd be willing to wager a large sum NONE of you will do that.