> No protective magnetosphere... brutal temperature shifts

Not a problem in a shielded, climate-controlled shelter, e.g. one partly underground or in a cave.

> more radiation than you can reasonably survive on the way to Mars.

Putting food and water between space and interplanetary astronauts is a popularly-discussed option.

I think you may have been down-voted on your tone. This is an optimistic, bleeding-edge project. Unless you are an expert, it is more appropriate to ask why something isn't a problem than to prematurely declare it as unsolved or unsolvable.

I think the burden is on the person saying, "To mars, very soon!" to explain what they feel has changed, or changing, to allow that to be something other than a one-way, dead-end mission.

If you want optimism for the sake of optimism, Facebook has some lovely mother's groups.

That's an arrogant perspective. What value are you adding that anything needs to be proved to you?

...Or maybe we have? I see the downvotes, but no replies to explain what I missed.