As a matter of fact, population growth due to births in developed countries drops very low- IIRC, the U.S. fertility rate is actually below replacement levels,

As a matter of fact, population growth due to births in developed countries drops very low- IIRC, the U.S. fertility rate is actually below replacement levels, and fertility in Japan is so low that people worry about a majority of Japanese being retirees in coming decades. Furthermore, as still-developing countries catch up, they follow the same pattern. There's every reason to believe that sufficiently advanced human populations do indeed control themselves. Not to say I agree with marincounty's vehemence on the issue, either. The key is to give everyone the opportunity and environment that allows sustainable reproduction levels, not to browbeat them into doing so.