The more I've learnt about space, the more I doubt we'll go past LEO for quite some time.
Take for example, the ISS, all it takes is a piece of debris no bigger than a marble to be on the right trajectory and it will be destroyed, the
astronauts staying on board have had to evacuate to a Soyuz capsule just in case on a fairly regular basis. This debris often is from us which
presents another issue and one someone mentioned earlier about having all our crap in space, there is already too much up there, it's a bloody mine
I think Zorgon did a thread on space garbage, or a post and if you ask me, we're pretty flippant about the whole thing.
So once we get past our own debris, we have to worry about things like asteroids, cosmic particles, solar radiation, cosmic radiation, and all sorts
of nasties, space isn't some sort of empty vacuum I'm afraid to say.
So, all this leads to some sort of shielding, before we can have space hotels or moon colonies we need to build them so they are able to protect
themselves from these things. I think this is the next big hurdle, we have the propulsion tech, we have the ability to be self sustainable but we
can't fully protect ourselves from pace itself yet.
The second problem is money and the entire planet contributing together, already mentioned I know but two things come to mind here...
Star Trek and what ATSers would call the NWO.
Firstly, taking a leaf out of Gene Roddenberry's vision for space is probably the best way to go about it, when you break it down, the guy had the
Namely, a one world government.
Now, many here believe this is being put in place as we speak and that it's completely evil.
If the mass human exodus to space is to happen, we'll need this one world government.
Anyway, just throwing what's in my head down, there's a whole not more obviously.
It will be a tough ask whatever we do!