[ustolemyname]

I'm going to nit this for several reasons:

1. Walking on the moon implied a return trip which requires an extra ~3km/s.

2. Under the rocket equation the fuel requirements for more delta v grows superlinearly, which then awkwardly makes your rocket bigger, which requires more fuel...

3. 22 years prior a metal can went to space. The scale of a manned moon mission in comparison is absolutely nuts, even basic things like having rocket motors that can be relit is a large technical challenge.

[mhh__]

Addendum to point 3. It's not just a metal can, it's a metal can with some people in it. You have to keep them alive and useful for roughly a week, not just fling them at the moon.