The thing is, you can substitute "politics" for "people" and get the same statement, which is why NASA's political work is at least as important to human space exploration (and, I would argue, long-term species survival) as the raw scientific work.

People have to be continually convinced that exploration of the solar system is a worthwhile expenditure of a lot of money that could be spent on other things. Seems obvious to those who are already thinking in the direction of where humanity is going, but most people do not.