Globalisation means many other countries are asserting themselves and trying to take over leadership. Please don't ask Americans to let others assume the leadership of human exploration. We can do wonderful science on the Moon, and wonderful commercial things. Then we can pack up and move on to Mars.
Buzz AldrinWhen you're in a spacecraft, you need to know what things you can touch and what things you shouldn't touch!
Buzz AldrinExploring Mars is a far different venture from Apollo expeditions to the moon; it necessitates leaving our home planet on lengthy missions with a constrained return capability.
Buzz Aldrin