You've made the America comparison earlier; I just can't agree with you. This is a hundred times harder even taking into account newer tech. There's no *air* ferchrissake! For all the hardships that America may have had a few hundred tears ago, it did have plentiful flowing water, wood, food, vegetation, air.
Like I said, it's like Antarctica - but nowhere near as pleasant, lacking the water and air to be found down there. And civilisations ain't exactly springing up down there, for good reason! We have camps and settlements, but people can leave via helicopter and have stuff flown to them easily - there's no leaving Mars.
I agree with Morrus here. It's why I mentioned that here on earth, I can be dropped off with an Axe and a knife and be just fine. I can forage for foood, make weapons or traps to kill food, or tools to farm. I can build a shelter quite easily with an axe.
All with relatively cheap and primitive implements. the probability of an equipment failure is minimal, and I may be able to do without them if they did break.
In space, there is no food or air but that which you bring with you. You can't forage for it on Mars. Lose your supply, and you are hosed.
If your processing gear for air/water/whatever breaks, if you don't have a spare part or supplies, you can't do without or fix it with local materials. There's no plants or animals to make duct-tape out of.
This is hyperbole, but I'd say it's an order of magnitude more dangerous than colonizing any place on earth.
In antarctica, odds are good you aren't losing your parka. You can melt and eat snow. You can eat a penguin. And you can sort of sail back home.
Granted, under sea living or antarctica is the most dangerous places on earth, there's still a few more escape clauses and options there, than you'll have on Mars.
