Over 300,000 (mostly) skilled jobs were created for the Apollo space program and 181 Billion dollars returned on the initial investment of 25 Billion.
The proven success of job creation, economic stimulus, and return of investment should provide a platform to help outline and forward the goal of permanent manned colonies on the Moon and Mars.
The settlement of the Moon is a logical step in the expansion of humanity beyond the Earth. There are many good reasons to create permanent colonies on the Moon, including scientific observatories and future industries
Wikipedia - http://en.wikipedia.org/wiki/Budget_of_NASA#Economic_impact_of_NASA_funding