Let's talk about iMessage (again)

Yesterday's New York Times carried a story entitled "Apple and other tech companies tangle with U.S. over data access". It's a vague headline that manages to obscure the real thrust of the story, which is that according to reporters at the Times, Apple has not been forced to backdoor their popular encrypted iMessage system. This flies in the face of some rumors to the contrary.While there's not much new information in here, people on Twitter seem to have some renewed interest in how iMessage works; whether Apple could backdoor it if they wanted to; and whether the courts could force them to. The answers to those questions are respectively: "very well", "absolutely", and "do I look like a national security lawyer?"As the article states, it all comes down to trust.