And the desire of anyone with the ability or funds to do it to go to space regularly enough to need it.
It's like proposing to the East India Company to build a modern mammoth tanker. They would not understand why anyone would want to transport such quantities of material across the ocean. You can't really blame people for not having a clear vision of the future though.
When I think back to being a kid and how space felt like the future, it makes me sad that typically it seems like no one besides researchers gives a shit anymore. I used to watch Star Trek and knew it wouldn't happen in my lifetime but it felt like that was the eventual goal and the direction we were heading in. Now I see it as the fantasy it is, because without some compelling financial gain in taking trips up there for anything besides tourism for the super-rich, I think we are going to stay stuck on this rock.
I disagree.
Firstly, we have some exciting missions to planetoids. Pluto and Ceres are about to be visited (spacecraft is already on its way).
Secondly, the ISS is a great success of global cooperation. And now it is being supplied by commercial parties, at lower cost than ever. And the fact that it's up there (it's huge in comparison to anything else we've put in space) is a sign we're moving forward.
And then the Chinese are breathing down the necks of Western space agencies, and catching up quickly. Thereby ensuring that we don't get lazy.
And finally, I really believe that this idiotic Mars One program can be a success. The global budget for advertising is simply insane, and if they would only capture 1% of the advertising money, they can totally build a Mars mission. It needs to gain popularity, but in this modern age, that is not rocket science.
Sure, the massive budgets of the golden days of the space race are over. It's all a bit more sensible now. Until the entertainment industry steps in!