We have posted many times about the tragedy of the commons here. This handy concept goes far beyond the original meaning.
It is the most basic human nature to take care of your own. Unless you have a close, small, closed society with strong affinity and who are on the same page, people will rape the commons for their own purposes.
We posted the other day about plans to try to maintain the fisheries.
John Stossel discusses Eat the Tigers! Same point. Most people need a sense of ownership to really care about stewardship.