The passport is for Americans, all others can cross at will.
No tengo passport
I seriously doubt that they're giving away "military secrets". Mode 2 IFF is what I'm thinking they're referring to, and if that's the case, that has never been classified. There are far more dangerous "secrets" that have been compromised by past administrations and spies (John Walker and his ilk). I doubt some form of IFF is going to destroy our military aircraft.
However, I DO see the security issue brought up by:
Cargo-dog airliner loaded with explosives at some Mexican airfield. Check.
Flown right into the Texas oil refinery ports or a skyscraper in any major city. Check.
Brilliant.
Canada doesn't seem to bother me as much as Mexico, BUT, there are FAR more radical Islamics that roam freely about Canada. Hell,l I think we have more than enough of them right here in the good ol' US of A