Tangential home run
The real problem is is not energy consumption, nor pollution, nor lack of food production, but the true elephant in the room that few are willing to speak of, let alone seek solutions for...that there are approximately twice more than the sustainable number of people on this planet. Much as I hate to approve of anything the Chinese government has done...and I absolutely abhor some of the methods they use...they are the only country to seriously address this issue. Until you can convince the rest of Asia, Africa, South and Central Americas and Mexico to adopt negative population growth solutions, the human race is pretty much doomed. I will point out that were it not for immigrants from those same areas, the U.S. and Canada would already have achieved negative population growth. I don't have accurate numbers for Europe or Australia. We passed the point where we (the human race as a whole) are willing to spent the trillions of (pick a currency) it would take to open up new frontiers for expansion off-planet at just about the same time as the technology to make it possible began to appear, half a century ago. Without one or the other, we don't have any hope of surviving as a civilization - or perhaps as a species - for even as long as the relatively short-lived nation of the United States has been around.
