They are only paranoid because they know they have introduced backdoors into products their countries produce. Do you really think the US/UK/AUS has not introduced something into a Cisco product or some other hardware manufacturer in their respective country.

Just look at what has come to light with the PRISM program. They already have access to the major software companies what makes people think they havent done some secret FISA order to Dell/Cisco/HP/Apple etc.

edit: typo