I don't think they're limited to "a thousand planes," I think that's just all they need
the capabilities of planes from ww2 and today are almost not worth comparing
the capabilities of planes from ww2 and today are almost not worth comparing
The F-35 is on back-order to the mid 2030s. Even superpowers can't make more than tens of planes every year.
It's just that the modern world is relatively peaceful, that's why they don't need more.