The Soviets earned the awe of the world in 1957 when they put the first artificial satellite into orbit, Sputnik. This was quite the PR coup, and was one of the motivators for the US national alarm about our lagging scientific expertise compared to the Soviet Union. That was probably a good thing for the US (investment in human infrastructure, we might call it today) -- there was a name for this US response but I can't remember what it was. But as I understand it, the Soviet coup wasn't due to greater knowledge, it was that the US military didn't think it was a priority. For the Soviets the ICBM was the first way to threaten the US homeland with nuclear attack (a rocket that can put a satellite in orbit can with a bit less power land a nuclear warhead anywhere on earth). The US already had ample ways of threatening the USSR from a variety of bomber bases right next to the USSR. In terms of the PR coup, what I've heard is that basically the US was asleep at the wheel and wasn't thinking along those lines. Of course the US took up the challenge, including Kennedy's promise to put a man on the moon, and we met that goal. That was our PR coup.
I don't recall any debate on whether we should go to the moon. The one snippet I have for an "anti" view was from Tom Lehrer. On one of his albums he notes that the US space program "will make it possible to spend $20 billion of your money to put some clown on the moon". Tom Lehrer was insightful about many things, but it seems he missed the boat on that one. I think most Americans thought it was $20 billion well spent, and much of the world population agreed. Pictures of the earth from the moon were valuable, and as a major human accomplishment it seemed to resonate with lots of people. I believe those 30-odd men from Apollo missions are the only humans who have ever gone more than a paltry 300 miles above the surface of the earth. Yet it didn't lead to much. I am reminded a bit of the dog who chases a car. The car pulls over, he's "caught" the car -- but now he doesn't know what to do with it. The moon is basically a big rock and there isn't much to do there. No one has gone back since Apollo ended, not because there are serious technical obstacles, but because there's not really any point.
Aside from the Apollo missions, human forays beyond earth have included a great many robotic probes. They explore various places in our solar system, and they convey valuable information back to us at relatively little cost. Getting humans to these places would be enormously expensive, especially as we need a return trip to bring them home safely. Our robotic craft are now far more capable than they were in the 1960s when the humans landing on the moon could gather some information better than robots.
We humans have for some years maintained the continuously-manned international space station, in low orbit around the earth. It is interesting for studying how things work in prolonged weightlessness, but I haven't heard of any truly astonishing discoveries that have resulted. Only 250 miles above the earth, it requires frequent rocket arrivals from earth to keep it going. It would be interesting to know how many earthlings know it is there, and of those that do, how often they think about it.
But what are the prospects for sending more humans beyond near-earth orbit?
There are a fair number of smart people who have in mind the idea of space colonization -- that humanity will spread throughout the galaxy. To a lot of other smart people (and me) this seems crazy.
On earth, exponential growth allows organism to grow from small beginnings to occupy large areas. The space-colonization enthusiasts see humans doing this from star to star throughout the galaxy. Spreading humanity among the stars requires a great many planets to support the sort of economy we have on earth, using native materials to build more huge spacecraft, for instance. That is what would be required to let human expansion grow exponentially. We know there is no environment in the solar system that could possibly support that.
The nearest remotely suitable star is Alpha Centauri. There is no reason to think there is anything remotely habitable in that particular star system, let alone anything that would support a vibrant civilization. The requirements of a world that supports life in some form are far more lenient than a world that could support vibrant, flourishing human life. And to top off the list of problems, such worlds might already be full of other kinds of intelligent, vibrant, flourishing life that would not take kindly to human efforts to appropriate their world.
What about the more modest goal of just getting humans to another star? The obstacles are enormous. I found this brief write-up <rather amusing> (maybe I just have a quirky sense of humor).
Within the solar system, all space missions we can imagine require transferring enormous resources from earth to support the endeavor. We probably could set up a permanently inhabited station on the moon, but the rocket trips up there to support it would be unending.
A human trip to Mars isn't out of the question. It "only" takes 9 months to get there, given rockets we know how to make.
A permanent station on Mars is also a possibility, but once again the rocket trips to support it continuously are unending.
But these aren't just pipe dreams. Serious people in government bureaucracies seem to have <plans for this>.
Are these government pronouncements part of a calculation to support space budgets, figuring that popular support can be marshaled for programs with the human touch of sending humans? Does it lift human spirits to think we'll get to it "some day" even if never happens? Does it connect in people's minds to that goal of human colonization of space, however unfeasible in sober, practical terms?
For me, I'd say we made the point that it's possible to send humans from earth to other heavenly bodies back in 1969. We proved a point. From now on let's have the robots roam the solar system and beyond, and keep humans right here on earth.
<This XKCD> stayed with me. If you stop thinking astronomically, trapped on the surface of a sphere isn't a bad place to be.
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