Technology progression is not a given. Look at how stagnant space technology has been for the last 50 years. Living on a single planet is extremely risky. W

Technology progression is not a given. Look at how stagnant space technology has been for the last 50 years. Living on a single planet is extremely risky. We should minimize the time we spend as a single planet species. The earth is about 70% through it's lifetime, it won't last forever.