I cannot agree. Physically getting to Mars and setting up camp is a challenge. Physically getting to another solar system and setting up camp is a challenge to

I cannot agree. Physically getting to Mars and setting up camp is a challenge. Physically getting to another solar system and setting up camp is a challenge to the power of challenge. The numbers and difficulties are profoundly greater between the two. Self sufficiency is entirely possible given enough energy, material, and care. We've managed to do it for four billion years on this planet. There's no reason it can't be done on another planet, or a ship as you mention. I maintain that creating a stable-enough social structure that can survive offworld long-term seems to be most difficult part of the quest to leave Earth.