I loathe being mostly on the unpopular side of this debate, I really really do because I am deeply passionate about colonising other planets and exploring beyond our solar system, beyond our star system, beyond our galaxy, and maybe one day with enough exponential luck coming into contact with other intelligent life, or even discovering the relics of any advanced culture of extinct species, and all the inexplicably ultimately staggering possibilities all this opens to our race. Humanity as a collective needs to come together and put our greatest minds to the task of making these, inevitable necessities a reality (necessities in that, the earth is finite and humanity can potentially long outlast it). However disease and extreme poverty are problems we face immediately, and threaten to undermine everything I desperately hope humanity will express to any such intelligent life we are fortunate enough to be given the chance to exchange pleasantries and cultures with. Going out there, the odds are astronomically against us coming back with anything but a requirement for time and labour to put what we already have here, on there. What would our new inter-galactic allies think of us when they discovered, rather than ease the suffering of those already on our planet in their many millions, we decided to buy a new city? Well I guess that depends on if they're prone to mass genocide or violent xenophobia, but I would hope they'd value that life however futile and of limited significance it is. The NASA program was only a fraction of America's budget, but of humanities "budget"? Of the cities we could build here to home, educate and provide medicine to those who already need it. I can't justify that, especially when I consider how vastly humanity has failed those of us who hope beyond hope and put our all into furthering our species, when the rest of the world would rather gawp at dull witted uneducated marketing-clones in music / television / etc... and fill their lives with meaningless beyond futile (not to mention stagnating) bile. Humans on another planet would be like the humans here, lazy, opinionated without empirical or logical basis, and driven by the desire to get ever shrinking audio devices. Most of us would completely lack any modicum of appreciation of understanding of what we'd have achieved would we put them on Mars. This generation of humanity has yet to mature, allowing too many of it's own gaping wounds to go untreated. The wounds are festering, and we shall be judged forever as a species by how we treat our less fortunate and weak. Well at least judged until the universe ends since there is as of yet no conceivable means of surviving longer than it (Unless time travel is possible, but that opens a whole new complex web of arguments and problems). Humanity needs to grow up and acquire drive not for a solution petty squabbles, not from desire for financial or influential superiority, and certainly not to further the abhorrent "advancements" of the fatuous and misguided. If we send humanity to colonise space we benefit only the few who would use it as a platform to much greater achievements ad infinitum.
In conclusion, the issues those who you passively mocked with the whole "hypochondriac" and "nay-sayer" montage, are as relevant now as they will be to what we reveal ourselves to be to the universe and all it's potential for wondrous adventure and discovery and equally it's horrors and foulest spawn. Not only is it the very basest of human requirements we allow to go unsatisfied, but there are much greater threats looming ominously over our collective heads. The issue with energy is very real and all as if not more so important than space exploration, poverty or medicine. Global warming is really shit. It's beyond shit. It supercedes shit a billion fold. It is the single most prevailing threat to our existence for the significant future. Earth is nothing if not a test, a trial of what we are capable of, how we treat each other and our environment when we comprehend a little of that capability, and a lesson in how to sustain, to endure and to be prosperous. That's my opinion anyway.