Mercury, Gemini and Apollo were standins for open war with the Soviet Union, so they got more war-like funding and focus. 'Terrorists' aren't going to be shown up by space travel and no one believes we're really at war with the Chinese so no one is willing to throw money at it.
The US has never really funded anything that isn't related directly or indirectly to war, that includes Space Exploration.
The US has never really funded anything that isn't related directly or indirectly to war, that includes Space Exploration.