“I have nothing to hide. Why should I care if the NSA is vacuuming up my phone records?”

The news that the NSA has been indiscriminately collecting the phone and Internet logs of Americans under sweeping Patriot Act orders has provoked outrage from civil libertarians — and even Patriot Act author Jim Sensenbrenner (R‑WI).

But there are also plenty of quieter voices wondering why law-abiding citizens should be concerned about bulk data collection if there’s even an off-chance it might help stop a terrorist attack.

Polls aren’t necessarily great metrics of considered opinion in a case like this, but early surveys showed that a slight majority of Americans said they were basically OK with this sort of data dragnet. Presumably, many feel like the Manhattanite who told The New York Times: “Personally, I have nothing to hide, so it’s not really affecting me.” There’s even a Twitter account, @_nothingtohide, compiling tweets from Americans who cheerfully welcome our new metadata overlords.

Of course, few of these people truly mean that. Almost everyone has “something to hide” — if by that we mean some intimate corners of our lives we don’t want exposed to strangers, even if we’re not doing anything wrong.

That’s why the same polls show people aren’t nearly as comfortable with the government reading their emails and online chats. What they really mean, then, is that they don’t think a list of phone numbers and IP addresses will expose any of those intimate areas.

Yet folks in the intelligence community who actually work with all that metadata will tell you it’s often just as revealing as the contents of a call — even more so, once any kind of moderately sophisticated analytic techniques are applied to the data set as a whole.

Some of the potentially sensitive facts those records expose becomes obvious after giving it some thought: Who has called a substance abuse counselor, a suicide hotline, a divorce lawyeror an abortion provider? What websites do you read daily? What porn turns you on? What religious and political groups are you a member of?

Some are less obvious. Because your cellphone’s “routing information” typically includes information about the nearest cell tower, those records are also a kind of virtual map showing where you spend your time — and, when aggregated with others, who you like to spend it with.

It’s precisely this kind of analysis the NSA is likely interested in doing to help “fingerprint” either specific suspects or the general profile of a terror suspect. Link that information to other data sets being collected, like credit card bills, and you can even deduce when a woman is pregnant before her own family knows. Think of big data analysis as a statistical Sherlock Holmes, capable of making surprising inferences from seemingly insignificant details and patterns.

But fine, so what if a bunch of strangers in a room in Fort Meade could, in principle, discover these things about you? There’s no reason to think they’re digging for that kind of stuff, and even if they did, it’d be like learning there are naked photos of you circulating in a Mongolian village: A little creepy, maybe, but unlikely to have a concrete effect on your life.

Assuming you don’t match a profile that gets you flagged for more intensive surveillance, that’s probably right — as long as they’re only using that vast, rich database to look for specific terror or espionage suspects. If they change their minds about the rules governing access to the database or how it’s put to use, of course, we’re unlikely to ever know; we didn’t know what the rules were before the leak either.

That’s one problem with bulk collection of data. The information often sticks around indefinitely, while the rules only stick around until someone decides to change them. The IRS is all fired up to use big data to hunt for tax cheats, and in principle, the NSA can disseminate evidence of some crime. Sooner or later, other agencies may start to wonder why such a juicy data set is going to waste.

But the average person is unlikely to pique the NSA’s interest, even when those sweeping surveillance powers are abused for purposes ranging beyond terrorism. It probably won’t affect you personally or directly.

However, that seems like an awfully narrow way to think about the importance of privacy. Folks don’t usually say (aloud, anyway), “I’m white, why should I care about racism?” or, “My political and religious views are too mainstream to ever be restricted, so why should I care about the First Amendment?”

We don’t say such things not only because we care about other people’s rights as well as our own happiness, but also because we understand that we benefit indirectly from living in a certain kind of society. You may not be interested in protesting, criticizing the government or debating fringe political views — but as a citizen of a democracy, subject to the laws the democratic process produces, you’re better off in a system where those things are allowed to happen.

So, for instance, J. Edgar Hoover couldn’t have imagined the extent of the NSA’s omnivorous capacity to inhale, process and store vast quantities of information; he had to be more selective in his spying. If you weren’t a political radical, a union organizer, a critical journalist or a civil rights leader — like the central object of Hoover’s hatred, Martin Luther King, Jr. — you were probably never going to find your way on to Hoover’s tapes.

But you lived under a system shaped by Hoover’s attempts to destroy those people by quietly using information collected against them, whether through targeted leaks or direct blackmail. You lived in a world with an architecture of surveillance that granted chilling and antidemocratic power to a small group of men who operated in secret, feared even by presidents and generals. Hoover’s surveillance machine had nothing on the architecture of surveillance we are constructing.

Even when it isn’t abused — as far as we know — the very presence of that spy machine affects us and poisons us.Reading those New York Times interviews, you find acceptance, but also resignation. The attitude of the unemployed technician who sighed: “It doesn’t bother me because the government is going to do what they’re going to do regardless of what anyone thinks. There’s nothing we can do about it.” The construction worker, who accepted that “anything and everything you say, they could be privy [to].”

It’s slow and subtle, but surveillance societies inexorably train us for helplessness, anxiety and compliance. Maybe they’ll never look at your call logs, read your emails or listen in on your intimate conversations. You’ll just live with the knowledge that they always could — and if you ever had anything worth hiding, there would be nowhere left to hide it.