But those week-long stays during the Apollo program didn't establish a lasting human presence on the moon.
A lunar base could even become a thriving off-world economy, perhaps one built around lunar space tourism.
We can afford to get it wrong, and not kill everybody," former astronaut Chris Hadfield recently told Business Insider.
But many astronauts and other experts suggest the biggest impediments to crewed moon missions over the last four-plus decades have been banal if not depressing.
A tried-and-true hurdle for any spaceflight program, especially for missions that involve people, is the steep cost.
The Trump administration's immediate goal is to get astronauts to "the vicinity of the moon" sometime in 2023.
The political tug-of-war over NASA's mission and budget isn't the only reason people haven't returned to the moon. »