I like the space program (but not every project they have going on), and I agree that national defense is the proper Constitutional justification for such research; however I suggest you reconsider that particular line of argument -- the one I'm quoting in this post. Every left-wing spending program gets "justified" the same way ("We spend more each year on dog food than this little ol' program will cost!"), so it's the kind of argument that will justify literally anything.
I disagree, partially. One half of the argument - the cost - can be presented that way, and Democrats use it frequently. However, the other half of the argument - the gain - is completely different. This is not some "social sciene" garbage - this is a part of the technological foundation of our country. A critical one. It's my opinion that demonstrating just how little that cost is, particularly to simpletons that happen to be in congress or elsewhere, is critical to maintaining our lead. You must remember that although you and I, and others, may feel that money spent on space exploration, etc. , is money well spent, even if the amount is quite high, others don't feel the instant gratification they need from it, and are therefore critical. Simplifying that cost (in terms of a latte) is a rather effective tool in demonstrating just how little it is, especially to those who lack vision.