Nuclear war is possible but much less likely, compared to when the Soviet Union and the US were watching each other "knowing" the other was itching to launch, and so if they do you better attack back first lest you lose. Acid rain is still a problem, but not nearly the problem it was 40 years ago. The economy has always been kinda hosed about something - but overall your standard of living is better than it would have been. There have always been endless wars - where they are have changed over time. There has always been slavery, again much less today than years ago. I have seen newpapers from 1880 (not a typo, in the 1800s) where the editors were wondering what they would do when the oil wells went dry.