“The problem is twofold: first, there is no known general-purpose computer that can execute all the programs we can think of except the naughty ones; second, general-purpose computers have replaced every other device in our world. There are no airplanes, only computers that fly. There are no cars, only computers we sit in. There are no hearing aids, only computers we put in our ears. There are no 3D printers, only computers that drive peripherals. There are no radios, only computers with fast ADCs and DACs and phased-array antennas. Consequently anything you do to “secure” anything with a computer in it ends up undermining the capabilities and security of every other corner of modern human society.

“And general purpose computers can cause harm — whether it’s printing out AR15 components, causing mid-air collisions, or snarling traffic. So the number of parties with legitimate grievances against computers are going to continue to multiply, as will the cries to regulate PCs.

“The primary regulatory impulse is to use combinations of code-signing and other “trust” mechanisms to create computers that run programs that users can’t inspect or terminate, that run without users’ consent or knowledge, and that run even when users don’t want them to. The upshot: a world of ubiquitous malware, where everything we do to make things better only makes it worse, where the tools of liberation become tools of oppression.

“Our duty and challenge is to devise systems for mitigating the harm of general purpose computing without recourse to spyware, first to keep ourselves safe, and second to keep computers safe from the regulatory impulse.”