What do you mean a theoretical problem? It can happen - just because you can't imagine it happening or that it might happen years, decades or centuries from now, does not make it any less real.
I tend to agree. From my point of view, polio doesn't exist in this part of the world. It's as phantasmal as an asteroid.
Deadly asteroid is not a theoretical problem. Just a matter of when.
No matter what there will still be more than 7 billion people left on earth.
Surely developing the technology to deflect a killer asteroid is orders of magnitude cheaper than the technology to colonize Mars.
Can we not work on all the problems in parallel?
Not actually. An impact is inevitable, given enough time.
given the time scale of the duration in which a major impact event is likely humanity's technology will have advanced radically beyond which we could possibly imagine
Yes, and the way that will happen is that money will be invested into space technology companies like SpaceX.
or it will just happen anyway over the course of thousands of years
No, actually, if everyone chooses "invest in other things" over "invest in technology", then it won't happen. If it will happen, it will be because of technology investment, not as magic that occurs independently of them.
It's impossible to imagine how humanity would stop investing in technology or would only invest in technology that would not be related to space travel
If we go to Mars then for that population wouldn't lots of viruses be a theoretical problem?