It could also be said that an all-out war on cancer would allow humans to survive better in the harsh environment of space. As a geek I like the idea of space exploration, but I don't think it is the only way, or even one of the better ways, of driving technological progress.
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The space program was obvs a war effort. But I view war as one of capitalism's ways of managing the problem of overproduction. When we can substitute other outlets (eg space instead of war) for that part of the business cycle we should jump at the chance.
Don't underestimate the power of poetry. In the 60s we used the poetics of the moon landing to fund research. This was an innovation, in that previously we could only get that kind of money together for war projects.
So I see space as the poetics that saves us from spending all our money on war.