Privacy was a big deal when I was growing up in small-town North Dakota — mostly because there wasn’t any. From party lines to rural postmasters who made a mental note of your bills and letters, confidentiality was as rare as neighbors who didn’t gossip.

My mother adhered to just one strategy: When you turn on the lights at night, always pull the shades.

Ah, simpler times! Those were the days of “The Man From U.N.C.L.E.,” when the specter of spying seemed the realm of sneaking Russians. We felt sure that Boris and Natasha had no interest in everyday Americans. We know now how that turned out.

In the meantime, though, advertising graduated from clever cartoons and unshakeable jingles to psycho-science. By the 1970s, ever-eager advertising geniuses already realized peddlers of Coke, Kleenex and coffee could target customers far more effectively than by merely plunking their ads amidst episodes of “Bonanza” or “Beverly Hillbillies.” By divining consumers’ deepest dreams, fears and quirky notions, that faceless mass audience could be sliced and diced into far more precise profiles. That’s the moment when diving into your personal data emerged as a high art. To this day, it’s the life force of scientific selling.

Today America claims to be shocked — shocked! — that Facebook has been keeping track of the personal minutiae that we toss with little thought into its pixelated maw. Worse, the social media steamroller has been tabulating that data all along and selling it — gasp! — to companies that seek to turn our tendencies into an overpower urge to buy stuff we don’t need and ideas we didn’t think up ourselves. We are revolted by disclosure of the private facts we’ve freely flung into the web-o-sphere. It’s so bad that very old men in Congress who can’t recall their locker combinations are shown on TV grilling that young punk who runs the Facebook about the nefarious tricks of his trade: “Now, Mr. Zuckerberg, about these cookies … are they oatmeal or chocolate chip?”

Welcome to the world of advertising. The ways and the means are nothing new. All that’s different now is the scale on which it’s being practiced.

Of course, I, too, understand the creepy feeling when my secrets are being plucked from the ether. But like all the footprints you and I have left in our life’s journeys, the watchers have been tracking them all along. We seldom notice.

Compared to the low-tech lizards who’ve scoured public records and commercial transactions across the decades, 2018’s insidious technical wizards crunch big data like tyrannosaurs. Our discomfort stems from that speed and ferocity. Its black and heartless soul belongs to the shady warlocks of the web.

Yet their evil powers are really nothing new. We can draw a straight line from the birth of psychographics — market researchers who learned to probe consumers’ lifestyles and appetites in a sunnier, simpler time — to the dark arts now practiced by Cambridge Analytica and, indeed, state-sponsored cyber warriors.

Facebook is far from alone in basing its business on the time-tested TV advertising model: Create tempting programs to draw an avid audience, then sell their eyeballs to the highest bidder. Note, too, that the political manipulation that alarms us most is rooted not in the ethics of this long-accepted corporate approach … but in unauthorized misuse of what’s been gleaned.

Quite a few of my serious, thoughtful friends say they’re swearing off Facebook to protect their privacy. Too little, way too late. Unless you change your name, abjure all commercial contact and retreat to the bottom of the Marianas Trench, you’re on the radar — and have been in the crosshairs since Grandpa and Grandma were tadpoles.

Last month, Facebook promised to reveal whether users’ personal data had been hacked. I waited with bated breath. Here’s what I learned:

“Based on our investigation, you don’t appear to have logged into ‘This Is Your Digital Life’ with Facebook before we removed it from our platform in 2015. However, a friend of yours did log in. As a result, the following information was likely shared: Your public profile, Page likes, birthday and current city. A small number of people who logged into ‘This Is Your Digital Life’ also shared their own News Feed, timeline, posts and messages, which may have included posts and messages from you. They may also have shared your hometown.”

I was almost disappointed. No big deal.

My public profile is … public. My birthday and current city hold zero surprise. My Facebook “page likes” can reveal no arcane trove of jealously kept revelations (except, perhaps, that I really, really like cats). My politics? Look at my T-shirts and my bumper stickers — you can’t miss where I stand.

There’s not one single thing there that’s worth freaking out over. It’s already available in a hundred other places. If I ran into you in the produce department of Hornbacher’s — or, for that matter, Robert Mercer himself, the evil billionaire behind the move to misuse our most covert mysteries — I’d happily share all of that in a minute. And probably much, much more. If you were slow on your feet, in fact, I might talk your ear off before you could get away.

Privacy concerns are very real, but there are far greater worries that data gleaned from silly Facebook quizzes (what’s your pirate name? who were you in a previous life?). Russ’s and my credit card information, for example, has been caught up in several cataclysmic data breaches — Equifax, Target, Adobe. Meanwhile, countless government agencies and financial institutions maintain computerized records of every move we make. Are they secure? Wanna bet? Data hacking is a booming industry all around the world.

I can’t get too excited over social media’s revelations about my opinions — I wear them on my sleeve — or my most recent web search for a better kitty litter deodorizer. Fighting that fight is like flapping your arms at saplings while missing the very scary forest that engulfs you.

Let’s admit it: By and large, our secrets … aren’t. But when we turn on the lights at night, I still do like to close the drapes.