How many plants are needed to keep someone alive?

[Brother Oni]

I'm not saying the park wouldn't make sense, just that having all that airspace is a meaningful trade-off, and not a freebie.

I agree, as you have to consider the psychological needs of both the civilians and military personnel. As I understand it, even the illusion of open airspace is very conducive for mental health - even prisoners get some time outside.

Being permanently enclosed in cramped quarters takes a special kind of person - the patrol time of nuclear class submarines are only limited by the onboard supplies they can cram onboard before embarking and the psychological endurance of the crew - prospective crew are heavily screened for mental health before serving and even then bubbleheads are regarded as a bit of a weird and unique bunch by the rest of the Navy.