Chip: Contrary to the rants of libertarian loonies like Ransom, you are correct. The bigger picture is that what is needed is a continuing serious space program. If you have the assets to get it there, a decent-size nuke could deflect a small asteroid enough to miss the earth.
When the gov't works for the common weal (e.g., put a man on the moon, build the Hoover Dam or the Interstate highway system), it generally is inefficient and wasteful, but it works. When the gov't attempts to take care of individuals (e.g., welfare, Obamacare) it generally does a lot more harm than good.
We are not bankrupt because of NASA or even military spending. We are bankrupt because of entitlement programs.