Interplanetary Migration a Lifeboat?

I have two questions: where will you go, and how will you pay for it? Believe it or not, those are the key questions. To colonize Mars, for example, with 250 initial colonists and a serious terraforming effort which would achieve habitability within, say, one hundred fifty years would cost on the order of $25,000,000,000,000 to $50,000,000,000,000 (those are trillions of dollars). It would cost more if you had a continuous shuttle from Titan, a moon of Saturn, to bring in nitrogen--which would be cheaper than importing it from the Earth. I'm not saying that you're wrong to think about these things, but one does need to consider the practicalities.

No matter where you go, you can't escape yourself.

Even if this was doable in terms of funding and political goodwill, you have to consider that travelling outside of our solar system is going to cost decades, or perhaps even centuries. The generation who arrives at the target planet is not the same one that left. And even if there was a way to measure which humans are 'most' willing and capable of achieving 'sustainability', who is to say that their children or grandchildren will feel the same way?

Yes, I agree that's the problem; but my point is that when you read opinions that humans should first learn to steward the Earth sustainably before thinking about colonizing other planets, the assumption is that we're all in this together.

In reality, many people don't care about sustainability or they don't really think there is unsustainability anyway. They just assume everything will work out in time, and they don't care because they'll be dead and they don't care about their grandchildren's grandchildren beyond whatever generation they will physically interact with while they are still alive.

So the point is that those of us who really care about sustainability may finally give in to the possibility that we just don't have the power to convert the rest of humanity to cooperate in achieving sustainability on Earth. At that point, we can migrate to another planet, but we would not want to do it if there's a chance others would take over our operation/ships and leave us stuck on Earth as it is run into the ground by people who don't care.

I don't think it really matters if you can measure who is really most willing and capable of achieving sustainability because whoever leaves Earth will die 'en route' and their children or grandchildren will be the ones who arrive at the new world. You would have to trust that your progeny would honor the values of sustainability and be intelligent enough to steward the new planet according to those values. And of course there's the risk that future generations will get greedy and turn the new world into an unsustainable profit-market like present day Earth, but it is doubtful that interplanetary/interstellar trade would be attempted, unless there are things that can be shipped back and forth to Earth that can be in transit for 100s or even 1000s of years that will retain their value over that long a duration.