You'd be surprised. Anything....ANYTHING that has to deal with a military vehicle of any sort has strict rules surrounding it about who can see it. Even something as small and insignificant as a bolt for an engine mount cannot be shown/manufactured anywhere but the United States unless you get Defense Department approval first. See ITAR [wikipedia] for more information.

DUH DUH ... MITCHELL

Can't tell you how many times I've seen that episode.