A self-sufficient Mars colony isn't easy, but it doesn't seem impossible. And the lack of FTL doesn't really limit us to this solar system either: generational

A self-sufficient Mars colony isn't easy, but it doesn't seem impossible. And the lack of FTL doesn't really limit us to this solar system either: generational starships with nuclear pulse propulsion [1] could get us to the next star with around 100 years travel time. Not exactly something we want to start tomorrow, but fairly feasable. 1: https://en.m.wikipedia.org/wiki/Nuclear_pulse_propulsion https://en.m.wikipedia.org/wiki/Nuclear_pulse_propulsion