> Also, you miss the context of GP's comment by pointing the discussing in this way. They were replying to another comment that claimed cutting emissions was a difficult problem for reasons that are more... physical, I suppose you could say. GP was merely pointing out that technical challenges are not the obstacle holding us in our current predicament.

I don't agree with that. I don't see anything in the comment indicating that they saw the problem as anything other than easy to deal with. Have a look at the reply they made to me, where they said "if we would collectively stop chewing our cuds, it would be cheap and simple to do those things". That's still trivialising the social/political component, making it out as if somehow it's just a matter of making a choice as a society. You can't just wish for society to change its attitude, and while it's easy to talk about making such changes, there's the very difficult process of actually making those changes happen.

You might as well say "if we would collectively invent an infinite, completely clean source of energy, it would be cheap and simple to solve the problem." Well, sure. But that's just stating a goal. It doesn't mean it's easy to reach that goal.

The space sail idea is already designed for a scenario in which global warming becomes an even clearer and more urgent existential threat, causing countries to get together and devote a trillion dollars and a team of scientists to a radical solution. Given that context, I think it's reasonable to point out that in a scenario with money and collective will, we should stop polluting, whatever other steps we take.