Star Trek, whether it intended to or not, often anticipated our future. The timing may have been off, but technological progress suggests that Roddenberry and the writers may have had a touch of prophecy in them. However it wasn't always about technology.
Space Seed, starring Ricardo Montalban as Khan, suggested that Earth went through an Eugenics War in the 1990s. No such war has occurred, but over at The Energy Bulletin a speculative article about sustainability and population control raises the specter of eugenics as it asks the really hard question: How do we create and maintain a world of sustainable resources? What will it look like and how will it operate? Like it or not, we may find that the Earth's population exceeds the planet's carrying capacity. We cannot assume that technology will solve this problem.
Whether it's Hitler's Final Solution, the one-child policy of China, forced sterilization of people labeled unfit to have children, or some other eugenics-based population control methodology, we are talking about balancing the rights of the individual against the need to manage Earth's resources, especially in an energy-constrained world. Do we let nature handle it, or do we step forward and set the boundaries ourselves? What is fair, appropriate, equitable? These are rhetorical questions today, but what if they turn out to be more than rhetorical in the future?