“There’s already a door on that iPhone,” Mr. Comey said. “Essentially, we’re saying to Apple ‘take the vicious guard dog away and let us pick the lock.’ ”

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I like that. It’s describes the situation better than any of the other metaphors getting tossed around. The FBI isn’t asking Apple to “unlock” the iPhone. Apple doesn’t have the key. Nor does “backdoor” quite describe what Apple would be creating if it complied with the FBI’s court order.

But both Apple and the FBI can agree that what’s keeping the FBI from guessing the iPhone’s passcode by trial and error (i.e. “brute force”) are the three anti-hacking provisions in the latest versions of iOS:

• A 10-tries-and-wipe feature
• Built-in delays between pass code attempts
• The requirement that pass codes be entered by hand, not by computer

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The guard dog metaphor also helps elucidate why Apple created those security features in the first place: “We’re at war,” said Apple general counsel Bruce Sewell, referring to the increasingly sophisticated cyber attacks coming from hackers, organized crime and, he might have added, the U.S. government.

Once the snarling dog was in the hearing room, it never left. It became the operative metaphor of the five-hour hearings, referenced by one congressperson after another.

Also noteworthy:

• FBI Director Comey’s acknowledgement that the iPhone’s security features had frustrated “all parts of the U.S. government,” including, presumably, the National Security Agency.
• Manhattan D.A. Cyrus Vance’s assertion that “criminals know that the iOS 8 operating system is warrant-proof,” quoting a prisoner caught on wiretap describing it as “a gift from God.”
• The way Comey’s rote answer to knotty problems (“The judge will have to sort that out”) cut the legislature out of the solution.
• Rep. Jim Sensenbrenner (R-WI)’s surly warning to Apple. “You say that Congress should act. I can assure you that you won’t like what Congress does.”

For more on Apple vs. FBI, watch this video:

Quote of the day, courtesy of Comey: “It’s not a technological problem; it’s a business model problem.”