About war: in our universe we got the first digital computers because of military efforts during the second world war. However, without a war IBM and Konrad Zuse and others would have gotten there, too. With much less human suffering.
Most US investment in associated tech - including the Internet - came through DARPA.
Not pointing this out because I support war, but to underline that the US doesn't have a culture of aggressive government investment in non-military R&D.
NASA and the NSF both get pocket money in budget terms. And at its height Apollo was a Cold War PR battle with the USSR that happened to funnel a lot of of money to defence contractors.
The original moon landings were not primarily motivated by science.
So I think the opposite: we are way past the point of space exploration being directly useful for weapons.
Just don't spend tax payer money.
(And, if you don't like the monetary framing: just look at the real resources spend instead.)
However I'm not nearly as harsh on unmanned space exploration.
1) It's better aligned with mission profile (inspirational, emotional, but not strictly necessary;
2) There's much more of it to go than NASA gets;
3) It would be a better use of that money than what it's currently used for.
We'd get more and better science by spending it on unmanned space stuff. Or you could even just leave the money with the taxpayer.
