Space flight has a defense component, just as it always has, but space flight is not inherently a defense endeavor. Space exploration, and civilian experimentation such as the work done on the ISS are not military projects that have any relevance to the national defense. The exploration and civilian endeavors are pretty clearly delineated from military and defense missions. So, when talking about public-funded space flight, it's pretty clear we're not talking operations under the DOD, but the exploratory and civilian missions that seek to expand our knowledge of the universe, and have been undertaken in a cooperative nature with other nations in the spirit of shared origin and cause.