Top government officials have been defending the NSA’s secret collection of phone records of every American. But the argument they are using today to justify mass surveillance of phone calls could be used to justify ANY amount of intrusion into Americans’ private lives. Imagine, for example, what would happen if it were discovered that the NSA had placed a secret microphone and video camera in the living room and bedroom of every home in America. It’s easy to predict how the government would defend that kind of spying. Here is what they would probably say:

The audio and video data collected from Americans’ homes do not constitute “surveillance” because nobody watches or listens to the recordings, unless they obtain a warrant. Actually, not a real warrant, or even a subpoena, but permission through an internal NSA process based on—trust us!—very, very strict criteria. Or in a small number of other very exceptional circumstances.

The program has been approved by the chairs of the major congressional intelligence committees, as well as the secret FISA Court.

While it’s true that even the sweepingly broad Patriot Act requires that data be “relevant” to an investigation, there has never been a requirement that every piece of data in a dataset that is turned over be relevant, only that the data set be generally relevant . When it comes to the mass of data that we are collecting from people’s homes, we know there is relevant information in there, and if we don’t preserve that data, we won’t be able to find it when we need it.

At least 50 acts of terrorism-like crimes have been prevented. We can’t release details of these successes, but they include several people caught building bomb-like objects in their kitchens, two instances in which women who were kidnapped years ago were found being kept prisoner within private homes, and numerous instances of domestic violence.

All of the arguments above are essentially what the NSA’s current defenders have been saying. My point is that there are few limits to the spying that their arguments could be used to justify.

The idea of the NSA secretly visiting every home in America to hide audio and video bugs inside may seem far-fetched, but what they have actually done is not quite as different as it might seem. It was not long ago that in order for the government to collect telephone metadata (all telephone numbers called and received), the authorities had to attach telephone bugs known as “pen register” and “trap and trace” devices to a home’s physical telephone line. Today it no longer needs to do that, but its mass collection of telephone metadata accomplishes the same end through virtual means, and just because the technology makes it possible to carry out such spying through the reshuffling of digital files at telephone central offices, doesn’t mean it’s any less intrusive than if the NSA were to physically attach a bug on the telephone wires outside every home.