But why? I'm not against the idea in principle, but there has to be a motivation beyond "It's possible". Even the search for knowledge, which is a good reason to invest in R&D, but how much would we learn on the moon for that 2 trillion that we couldn't learn more cheaply through other means?
"what could we learn?". that's an interesting question. something unexpected I'd guess.
but that's rather beside my point.
Seems like a better use of money than weapons and killing each other with said weapons on Earth