Nothing wrong with optimism if it gets you through the night. Based on the vid, it would appear that what mankind has coming if we don't change our ways, is unlike any other challenge that has ever been faced. I am not so optimistic, when I hear the neighbor starting their car thirty minutes or so before going to work because it is a little cold outside, or often cars kept running for the air conditioning, when people are shopping or at the post office in the summer. Too many dead heads out there to make meaningful changes, you can't really force people to get smart to the extent that is required.