>It has water, mineral resources, a CO2 atmosphere plentiful enough to consider using it as an industrial feedstock, soil that we know you can grow plants in, a 24 hour day/night cycle, and enough sunlight to support crops.

Mars' atmosphere has only 20 times more CO2 than Earth's does, CO2 is not a rare chemical. We don't know enough about Martian soils to be sure that we can grow crops there.

>Mars will be analogous to North America in the 16-20th centuries.

I see this analogy around a lot and I've never cared for it.

1) All successful settlements of Europeans in the new world had some economic purpose for existing. The first few attempts to settle North America by English settlers were dismal failures until they discovered that they could grow valuable tobacco there. What is Mars' tobacco? We'd need a product that is cheaper to manufacture on Mars and ship back to Earth than to make on Earth. We need this because...

2) Mars is a vastly more hostile environment than the new world. It would have been possible to set up fairly small colonisation groups that were mostly if not entirely self-sufficient and thus didn't need to find economically sustainable products to sell to the home country in trade for vital supplies. In fact, later settlement in New England followed this pattern - many people paid for their passage and bought some land and only needed a few imported goods rather than the whole-sale re-supply that the earlier settlers in Virginia had required.

The minimum local knowledge and technology base was essentially simple agriculture at first, followed by some village-level craftsmen for simple tools and such. This meant that only a small fraction of the local economy had to produce goods for export because most things could be produced locally.

That is very far from being the case on Mars. The minimum technology base required to have a mostly independent colony on Mars is a substantial fraction of our entire tech base on earth. Even if we assume that high-complexity, high value-density things like computers and other electronics are imported from Earth that still leaves us with a lot that needs to be made on Mars. If we want to build another settlement on Mars from our initial base, can we do that?

Can we build the environmental management equipment needed? Pressure envelopes, power generation and distribution? Even something like light bulbs would be hard to do. Individually, all of these things are totally possible of but when you add them all together you start to require an awful lot of machinery to take with you.

The alternative of course is to keep supplying these things from Earth but without a sustainable source of goods to export back to Earth that isn't going to be sustainable.

3) The relative cost of transportation. Early settlers of the new world could use existing ships once they knew where to go. With Mars we know where to go but we don't have the ships. A moderately wealthy merchant could pay for the passage of his whole extended family to the Americas, even if the price drops dramatically that isn't going to be the case with a passage to Mars.

None of this is to say that I don't want to see permanent human settlement on other planets, but I think that comparing it to the settlement of the Americas is very unhelpful.