Besides, if we don't get things straight on this planet, we'll never be able to survive long enough to find another one.
Survival is an argument for getting a lot of people living off planet, not an argument for not doing so. We can try and create utopias as much as we like, but that is not going to help very much when we get hit by a big rock.
Also, personally I suspect that the real advance is not going to be in settling other planets, but building habitats out of asteroids.
http://www.planetaryresources.com/asteroids/composition/
Besides, if we don't get things straight on this planet, we'll never be able to survive long enough to find another one.
Survival is an argument for getting a lot of people living off planet, not an argument for not doing so. We can try and create utopias as much as we like, but that is not going to help very much when we get hit by a big rock.
Also, personally I suspect that the real advance is not going to be in settling other planets, but building habitats out of asteroids.