Singapore once waived your hospital bill if you got sterilized within six months of giving birth. It pushed third children to the back of the school registration line. That campaign ran 15 years and took fertility from 3.07 to 1.43. The reverse campaign has now run 39 years. The number today is 0.87. "Stop at Two" launched in 1972 and hit replacement level by 1975. It barely cost the state anything, because penalties are cheap. You make the third child slightly more expensive than the second,…