It doesn't need to go that deep. The biggest weakness in any system is at the human layer–think Skippy Podesta with his shitty password. All these systems have to have administrators, because the average person doesn't know how to computor (which is a horrible thing that never should've happened, c.f. Ted Nelson). Of those administrators, I can guarantee a good 50% are natural born commies. Another 25% or so are mercenaries, easily bought. The rest are dumbshits fresh out of the community college pipeline who have no idea what they're doing.
Point is, those people have absolute control over the system. No one thinks to question them because no one has any idea of how to question them–because, again, computers are magic to a good 99% of the popluace. If the people responsible for actually running these systems were comped, nobody on either side would even know because of that lack of knowledge. The admins are chokepoints.