Earlier quoted context omitted.
>The notion that we should be colonizing mars because of global warming is the stupidest thing I've ever read or heard. Yeah, because that's a strawman you imagined in your head. I'm not sure what gave you the impression that the two were related (other than that they're competing options) based on my previous comment.
Someone posted it upthread. You can replace any catastrophic event with global warming and it's just as facially stupid. Literally like the thought process of a child. It's completely divorced from reality.
1. We refuse to believe very bad scenarios until much too late. Doesn't need to be apocalyptic: The Titanic isn't sinking; all of Hiroshima must have gone silent because a telegraph cable was damaged and it can't possibly be the entire city destroyed, and even if it was the Americans can't possibly repeat it; the Cultural Revolution cannot fail; the King can't be executed for treason by his own parliament; the general can't cross the Rubicon; Brutus can't betray me.
I think many of those things would have been dismissed the way you're doing now.
2. Tech is changing. I don't expect extinction from a natural pandemic, but from an artificial one is plausible; not from a natural impact event, but artificial is… not yet, but no harder than creating a Mars colony; propaganda has already started multiple genocide attempts, what happens when two independent campaigns are started at the same time when both groups want to genocide everyone not in their group?
The same risks would still be present on Mars, and the only way I see around the deliberate impact risk is space habitats which have their own different set of problems (given we can't coordinate on greenhouse gases I see no chance of us coordinating on Kesler syndrome either in cis-Luna nor in Dyson swarm scenarios).
I don't have any solutions here, though.