Why are there no space colonies?

[Josephus]

Colonizing Mars is much, much more difficult than most SF writers realize (though many of the issues were unknown in 1963).  For instance, plant life needs a lot of phosphorus, and Mars has very, very little.  A self-sustaining Mars colony (growing plants in greenhouses, for example) would need tons and tons of phosphorous to be sent from earth.  Another essential element, nitrogen, is very uncommon on Mars and would require a lot of ore processing to extract (you'd probably need to choose the site based on access to nitrogen-bearing minerals).  You could get nitrogen from the atmosphere (it makes up a bit less than 3% of the atmosphere) but processing energy requirements would be massive.

So, the problem is that Mars lacks some of the basic elements needed for life in easily-obtained quantities, and there's no easy way out of that.

So everything you said is completely true.

But we haven't even gotten to that stage yet.  Humans haven't even visited Mars, never mind setting up self-sustaining colonies.

We're still at the stage that the distance is so great, that the amount of propellant and supplies is so great to get there, that we haven't been able to get that much into earth orbit in order to fly there and back.

And that's without worrying about the radiation on the way (and the radiation on Mars, which lacks a magnetosphere).

And also...why no Internet?

https://www.youtube.com/watch?v=wC3E2qTCIY8

Close enough 

[Valmy]

And that's without worrying about the radiation on the way (and the radiation on Mars, which lacks a magnetosphere).

Yeah. Any colony on Mars would need to be underground to protect us from the radiation I think.

[Valmy]

It would be incredibly expensive and not much upside.  Same reason we haven't colonized the sea bed or the interiors of active volcanoes.

Yeah we have 75% of the earth's surface uncolonized. Seems like we should be creating deep sea colonies before we go to Mars.

[Syt]

And also...why no Internet?

https://www.youtube.com/watch?v=wC3E2qTCIY8

[Sheilbh]

Going to blame NIMBYs, somehow.

[Josquius]

It would be incredibly expensive and not much upside.  Same reason we haven't colonized the sea bed or the interiors of active volcanoes.

Yeah we have 75% of the earth's surface uncolonized. Seems like we should be creating deep sea colonies before we go to Mars.

Or Yukon/Outback/Lappland/Wherever colonies.

[Razgovory]

The problem lies not in science or economics but philosophy.  Gayatri Spivak founded postcolonial studies and kicked the legs out of any colonization, space or otherwise.  By showing that the very epistemology that backed our science was a European imperialist construct that ignored the views of the subaltern she forced the US to adopt the less ambitious shuttle program.