I’ve argued that the future of humanity necessarily involves a future in space. There, we won’t have the room restrictions, resource restrictions, and catastrophe likelihoods that we’ll have so long as we’re confined to the surface of a single planet. There, a single nuclear, or nanotech, or biotech mistake won’t wipe us all out in the blink of an eye.
But to bootstrap into a space-faring civilization takes a huge commitment. Space travel (at least from the surface of the Earth)takes a LOT of energy, which (on average) we don't have to spare. Space travel (and bootstrapping our future) also takes money, which we also (on average) don't have to spare.
One key point of my proposed "space faring future" is that we will need fusion energy, which potentially solves the energy problem. We aren't there, yet, but there is hope. Out as far as the Asteroid Belt, solar energy can handle our needs, but in the very long term (think a thousand years) we’ll need to expand beyond there.
A second key point is that a future in space for humanity is not likely to involve a lot of travel to and from planetary surfaces. Landing deep in a gravity well and launching into space from deep in a gravity well is extremely expensive. I also don't believe that we will colonize Mars or even our moon to any great degree - there's just very little value in that, and a great deal of expense.
That's why I expect that humanity's future will be asteroid and comet based. Comets (and carbonaceous asteroids) provide all of the raw materials (including hydrogen and deuterium for fusion power) that we might need for a space-based civilization, in a readily accessible form. It is relatively cheap and easy to land/take-off from their negligible gravity wells.
However, to get there in the first place (especially with enough infrastructure to build a high-tech industrialized society) will take a lot of energy, which we aren't likely to have to spare until we perfect fusion energy.
I have another very important point, which I haven’t elaborated on the past, largely because it is too depressing.
I don't believe that the USA will be a significant part of humanity's future. We have too many well-meaning people who think our wealth should be spent in other ways, such as feeding the poor, burying excess carbon dioxide, low-income housing, building giant levees around all of our low-lying coastal cities, and (most importantly) preserving the status quo. They want to preserve what we have, or restore what we had, instead of building the future.
I believe that humanity's move into a space-based civilization will be funded by either extremely wealthy dictatorships (think oil sheiks) or other dictatorships that care more about results than about their people or damaging the environment - think China.
You see, we have more than enough wealth to create a comet-based space faring civilization. We could do it now IF we didn't mind launching large nuclear reactors into space (a nuclear submarine is quite similar to a spaceship, a nuclear-powered aircraft carrier could carry more than enough infrastructure and people to colonize an asteroid).
We don't have the needed wealth or energy ON AVERAGE. But there are people (or countries or companies or churches) that have enough wealth that, should they so choose, they could bootstrap the process, and in that way insure their own place in history.
It WILL happen. At least I hope it will - the alternative is likely to be the more-or-less slow demise of humanity, as our per-capita energy falls, as our per-capita wealth averages globally, as billions of people starve and technology fails.
The status-quo is not an option. In an ideal world, we would find a way to raise the global per-capita wealth to something like what we currently enjoy in western civilization (likely making US much wealthier than at present). In an ideal world, we would find a way to do that while reducing humanity's impact on our global ecology (sounds impossible to me). In an ideal world, we would find ways to feed our burgeoning population while leaving most of the world's natural resources untouched (some people argue that we have no right to take the food that sustains the other carnivores of the world, such as sharks, wolves, crocodiles, hyenas, etc.). Other people would argue that it is more important to preserve the endangered spotted sand flea than to build power plants, factories, or housing.
I don't think it is likely to happen in our current society. We have too many people who want to globally average our wealth, too many people more concerned with reducing our impact on the world than on building our future, too many people more focused on taking the wealth of others than on creating their own wealth.
The status quo is likely to lead to a greatly reduced impact of humanity on the global ecology. That will automatically happen when civilization fails and billions starve and we are reduced to a few tens of millions of people living on the edge of starvation in a non-technological world. The remainder of the world (non-human) is likely to recover quite nicely (perhaps minus a few thousand species that have or will die out because of our impact).
At some point in the future, SOME dictator will decide to move HIS society into space, "screw the masses". It WILL happen, and that dictator will thus insure his place in history. The USA is likely to be a small reference in a footnote about a failed civilization, otherwise forgotten.
My personal attitudes (I'm normally a perpetual optimist) and beliefs (I'm intelligent enough to see that there are extremely serious problems in the world) are in conflict. I see that we DO have the resources, but not the will to expend them, and our excess resources are dwindling.
It would cost us a few billion to capture an asteroid, a few billion more to turn it into a factory for Solar Power Satellites (helping the Earth below), a few billion more to create permanent habitats in orbit. The total expenditures ($10B-$20B for this one project) would be less than we spend annually on pet food, or cosmetics. We spend 10 times this on gasoline every year to fuel our bad driving habits and oversized cars. The largest source of wasted wealth may be our excess expenditures on health care: The USA spends DOUBLE the dollars per person on health care than do the 2 dozen counties with better health care (as measured by their longer average life spans). This is a waste of roughly $600 billion, of which perhaps 20% is due to malpractice insurance and procedures instituted only to prevent malpractice claims (not medically necessary). A tiny fraction of this ANNUAL expense would fund humanity’s future in space.
There are so many solutions that we don’t have the will to implement. High-density urban living. Public transportation. Electric cars. Health care without waste. Eating more vegetables and less beef. Recycling (really, we just need less of a wasteful attitude as represented by our use of disposable packaging). Solar power. Geothermal power. Travelling-Wave nuclear reactors (that consume radioactive waste).
Question: What do YOU believe are the long-term goals of civilization? What SHOULD we spend our wealth on?