The United States Drug Enforcement Agency is mad they can't crack Apple iMessages, even with a search warrant. Why? Because Apple iMessages sent from Apple-to-Apple devices are not traditional text messages, and they are encrypted.
iMessages are encrypted messages that can be sent between Apple devices, including iPhones, iPads and even Macs running the OS X platform. The service launched with iOS 5 in 2011and Apple publicly revealed that all sent and received iMessages would be securely encrypted.
DEA officials first discovered that iMessages could be a hinderance to their efforts when a real-time electronic surveillance under the Federal Wiretap Act failed to yield all of a target's text messages. The agency then discovered that the person was using iMessage, which bypassed the text messaging services of carrier Verizon.
Apple revealed in January that it sees 2 billion iMessages sent each day from a half-billion iOS devices, plus Mac computers, which gained iMessage support last year. iMessage accounts allow users to send and receive their secure messages across all their Apple devices.
Apple's apparent stymying of the DEA was revealed in a government intelligence note . . . which calls it "impossible" to intercept iMessages, even with a warrant. The note is entitled "Apple's iMessages: A Challenge for DEA Intercept."
This is another example of the government publicly admitting that civilian encryption is very powerful stuff. Don't confuse "encryption" for "passwords" because they are very different. Passwords are apparently easy to defeat. Encryption isn't.
UPDATE: TrueCrypt has fallen into disfavor since this blog post was published, although it still works for many functions. Here are some alternatives to TrueCrypt: https://www.comparitech.com/blog/information-security/truecrypt-is-discoutinued-try-these-free-alternatives/