Electronic surveillance

Can the government force Silicon Valley to spy on its customers?

Somewhere in the world — perhaps locked in a vault at Apple headquarters in Cupertino, California — Apple has stored a set of very large, very secret numbers that cryptographers call private keys. These keys give Apple — and only Apple — the ability to update the software on the hundreds of millions of iPhones around the world.

These private keys give Apple a tremendous amount of power. Its iPhones regularly contact Apple's servers for software updates, and users have no realistic way of checking what these software updates contain. That means Apple can reprogram the world's iPhones at any time to do almost anything the company wants.