We've had permanent bases in the south pole for 120 years now. It's not particularly fraught. It's not free, but with a small investment of money we're perfectly able to do it.

We can't colonize it of course, because The Antarctic Treaty forbids territorial claims. Not because we aren't able to build things in the conditions that exist there.

Mars introduces a lot of new challenges, but 120 years of technological development gives us a lot of new tools to address them.