I wonder how much we've learned from the Saturn V project where the majority of the crucial knowledge (including for the machines that build the parts for the machines that build the parts) was undocumented. Hopefully a lot but maybe we just forward evolve instead.

I'm always impressed that America's moribund manufacturing industry nonetheless makes prodigious amounts of expensive vehicles. It feels like one year I was hearing about the terrible failure that the F-35 was and the next year I looked up and we've got more than a thousand of them - enough to dwarf any other conventional air force.