Which is inversely correlated with the chances of it coming in any particular timeframe.
I'm the biggest fan of colonizing Mars, but my children know that if Daddy ever has the chance he is going to Mars to suffer, not to play. Mars will be hard and unforgiving. Life will be horrible for the first two generations at least. At no point will it ever be better than life on Earth.
> if Daddy ever has the chance he is going to Mars to suffer, not to play. Mars will be hard and unforgiving. Life will be horrible for the first two generations at least. At no point will it ever be better than life on Earth.
This reminded me of computer tech in its first approximation: hard and unforgiving. It took about 2 generations to make it into a ubiquitous mobile device. In about four generations AI will make space colonies possible. "And AI shall produce acomodations for adventurous humans and preserve them". Space seems first and foremost the realm of AI, embodying our outreach. We won't actually go to space unless a planet is discovered and farmed to be hospitable.
Bioterrorism strongly depends on the incubation period. Probably safe on Mars. Rogue nanotech - not unless it has AI. (Though gray goo is not considered very realistic nowadays, as we've realized just how hard even regular nanotech is, and how hostile the natural environment is to nano-scale mechanisms.)
Nuclear war is the big one. Mars colonization would be less about preserving human life, per se, and more about preserving an operational duplicate of the peak state of human civilization.
My opinion is that these are just be symptoms of our social mental state. We're the virus. We need to fix ourselves. Maybe space exploration will help us see a little more long term? Hope so.