From where I stand, the same thing can be said of the DoD.
Right now, I can think of several project that I have been involved with that had both NASA and DoD involvement (In the interest of full disclosure, I work for a small aerospace firm, so I am biased on this issue). There are some things that can get funded better by one agency vs. the other, but there is a certain amount of exchange between the agencies.
Could this be done better if it was all DoD? Perhaps, but there would be the appearance that all we were doing was militarizing space. That is not an easy sell to everyone, and would have been an even harder sell in the 1960's.
Let's allow the U.S. military to militarize whatever needs to be militarized, as long as it's in the best interests of our liberty.
The challenge is getting good leaders (unlike the current POTUS) to decide what are America's "best interests", and to make DoD run efficiently.
Let the universities, private research foundations, non-profit corporations, such as The Planetary Society etc. whether national or international, to do the science and exploration. Let Paul Allen and his group do the manned space flights for tourism.
I know, I know...private ventures don't have funding anywhere comparable to what the US government is able to pull out of its citizens and the Chinese banks.
Well then, the private ventures just better go out and raise the damn funds. If we had a Fair Tax in this nation, there would be plenty of private capital available for all kinds of private ventures, including manned space flight. But that's another topic for another thread.
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