I had this conversation with one of my work colleagues before I came back to University. I was trying to make a point that the world is becoming overpopulated and that there are only finite resources, and she simply focussed on the fact that she had 2 children, may want more, and that you can't take away people's freedoms like that.
But the act of good governance is sometimes telling people what they can and can't have, for the greater good and comfort of the population. Sometimes this telling is direct, as in a dictatorship, but it can also be achieved by making it harder to have children and taking away the benefits. But I feel that it has to be done.
I'm currently studying for a postgraduate degree in sustainable water management, and I have a particular interest in water resources. It is [wildly] speculated that in the future wars could be fought over water because as we get a larger population there is more stress, especially with climate changing and people living in water stressed areas (Las Vegas anyone). How can we feed this population increasing exponentially when we struggle to irrigate our crops, move water hundreds of miles and consume yet more natural ecosystems and landscapes to build yet another housing estate (SE England).
It's ridiculous. You have to control the breeding of people in certain stressed areas or we're just going to end up having ****ty little lives in the future.
The thing is, many governments don't want to encourage a stabilized population as more people = more economic development. In a capitalist world, how can you win the votes if your economy isn't continually developing/building debt/having a strong workforce.
I am a strong supporter of the Optimum Population Trust - see
http://www.optimumpopulation.org/