Ironically, at the time it would appear that the NSA was probably prohibited from spying on at least US-based Boing personnel. In fact, even today, they claim they'd be prohibited from looking at it(though not collecting it or analyzing meta data which is the whole problem) at least as far as the people involved are US Persons.

I think I see what you are getting at, but surely a trade with a foreign nation like Saudi Arabia - because the Saudi's are foreign, the NSA would have always had the remit to spy on the transaction?