At some point, we are going to run out of room.
Philosophically, what is the purpose of man if we cease to explore and learn?
I am a strong advocate of a space exploration program. For the past 50 years we have learned a tremendous amount through space exploration that has helped us in medicine, communications, geology, physics, etc. In Florida, it has provided a positive economic impact through tourism and jobs. 30a is correct that exploration is necessary for the future of mankind not only in expansion of our civilization but also for necessary resources to support civilization.
Now stating all that, perhaps it is time to work effectively at privatizing the space program. All of these items are NOT dependent on extensive government control. In the 1960's it was necessary for the government involvement, but times and capabilities have changed.
IMO, I believe that 20-25 years from now space exploration will primarily be privatized with governments contracting for services.