> One reason is that the Apollo program, which sent humans to the moon, was a major achievement for NASA and the United States, but it was also very expensive. The cost of the Apollo program, in today's dollars, was approximately $100 billion. As a result, there has not been a strong political or financial motivation to return to the moon.

This is less than the 10% of the current investment USA is doing only on the Air Force. USA spends 1,5 trillion anually on the air force only, not including marines, etc.