Look at the Middle East. It has a large concentration of very religious people. How do the various religions mitigate the issues arising out of large number of people living together?
--
In the U.S. religion has become very divisive. Forget about loving thy neighbor, Christian want to legislate their beliefs and force them on the un-believing. I believe in minding one's own business and I'm content to let others live their lives as they please.
--
Humans are ego-centric. I think this leads to an exaggerated view of our importance. We can't quite fathom that life will go on without us, so we make up myths to compensate. I used to agonize over this as a kid, but as you mature and age you see first hand that life goes on just find after those around you die.
--
Belief: I believe that we are a doomed species, unable to solve global problems because of our innate selfishness. Humanity as a whole is a giant organism devouring the planet in such a terrible fashion that it will be uninhabitable for future generations. As a whole we are not an intelligent species, because and intelligent species would pull out all the stops to save future generations.