Two sectors of the economy, that is: public and private.
The national railroad system and the Interstate Highway System were both products of the intersection of public and private interests. The nation's economic and military interests required an effective system of transportation; private business interests had the means to facilitate that through the invention and development of railroad and automobile transportation. Together, the public and private sectors were able to give America the land transportation it needed to unite the economic interests of the nation and give vehicles the mobility they needed for our national defense. And yes, a Republican president, Dwight Eisenhower, gets credit for the IHS (while simultaneously making Democrats wish there were more Republicans like him).
Why can't the same thing happen with space travel? NASA, although operating at a fraction of the budget it used to have, is still capable of producing incredible space-related technology, while private investors like Elon Musk are coming up with innovative new vehicles for reaching out into space. Maybe, if Washington, can get away from bickering, it could spend some time working on a way to get NASA and the Musks of the world to work together.
And get us back to the final frontier, so that we're no longer just exploring it in movie theaters and on TV screens.