It seems to me we give a lot of thought power about issues where we have very little solid information. Global Warming: is it good or bad? Do we have enough information to know how to stop it? (no) Will science discover that carbon dioxide is not the cause of global warming? On and on.
Earlier in this thread I quoted a source that has strong evidence that global population growth was slowing and may level off at 10 billion people. But who knows how people will respond when things start to get crowded? Look at Europe where the population growth rate is clearly downward.
These, and things like potential water/food shortage, etc. are well worth studying so we can get more solid facts. If we discover that action must clearly be taken to solve a clearly dangerous situation, then we can start talking from the basis of facts - not guesses.
Perhaps our largest problem is that most countries in the world do not want to work to together. A few weeks ago delegates from 190 countries around the world met in Doha, Qatar, to try to find some consensus about how to proceed - and the meeting was a failure. Each country is too busy looking out for their own best (short term) interests.
I have the feeling that we, and many other debates like ours, are wringing their hands about these subjects --- but right now human beings are simply going to go forward into the future. Right now it looks like we are powerless to change anything. Perhaps a scientific break through or simply change in human attitudes will provide a solution. But right now what will be, will be.