This is a good piece from Daniel Greenfield.
He's quite right-there will not be enough people to support the welfare state.
The thesis is very Steynian of course.
Related-just finished reading David ("Spengler") Goldman's book How Civilizations Die: (And Why Islam is Dying, Too) .
A friend urged me to read it because he found it made him very optimistic! I kind of rolled my eyes, but then I when I read through it, I realized why.
The only civilizations that are reproducing at an above replacement rate are religious Christians and Jews in Israel (both religious and 'traditional'). Everyone else seems to be going the way of the dodo bird.
Definitely worth reading. I recommend it.