If you really want to cry in your beer look at all the O'Neill colony art from the 70s. Some people were calling for colonies with populations of 10,000 by the turn of the century! (That's the turn of the 20th century.)<br /><br />On the other hand before the 60's even the most optimistic space advocates weren't expecting a moon landing before the turn of the century. Maybe the 80s or 90s if you were a real wild-eyed dreamer. In the 20s the majority of scientist and engineers didn't even think space travel of any kind was ever possible. The border between science fiction and reality was not nearly as porous as it is these days!<br /><br />The thing to keep in mind is that all of those dreams represent possibilities, not probabilities. just convincing people that something is possible is more than half the battle. The other half is the boring stuff (to us technophiles anyway)--economics and politics.