I especially agree with your point about Cisco trucks (although I think you meant Sysco, an important distinction since we are comparing food supply to networks). The fact is, there are plenty of ways to poison the food supply in our current society. Even ways that might minimize your ability to be discovered. And yet it is rarely tried. But networks are infiltrated all the time. I think partially because networks are accessible from anywhere in the world. No pants (as you said) or passport required.