Remember how boycotters managed to put a horrible, retrograde, right-wing beer company out of business? Progressives charged the brewer with unfair treatment of labor unions; discrimination against Latinos, blacks, women, gays and lesbians; and general association with conservative causes. The sheer breadth of the company’s alleged offenses marked it as an easy target. For heaven’s sake, the co-founder of the company was named Adolph.

That was Coors Brewing Co., and the boycott, which started in 1966, continues, at least for those social-justice warriors manning the last scattered foxholes in a war only they think is still raging.

Maybe the sixth decade of anti-Coors boycotts will be the one that works, but parent company Molson Coors sold $5 billion worth of brewskies last year with Coors Light continuing to be the second-best-selling beer brand in the US.

A similar story is the great grape boycott of the early 1970s. It was a thing. The United Farm Workers Union said grape growers were being unfair to the workforce. They tried to grab Big Grape by the little grapes. Today the boycott survives in the popular culture mainly as a line from the Woody Allen movie “Sleeper.” When Allen’s character is asked, “Have you ever taken a serious political stand on anything?” he replies, “For 24 hours once, I refused to eat grapes.”

With few exceptions, boycotts don’t work. There are too many of them, they’re too broadly targeted, our attention span is too short to remember what we were supposed to be outraged about months ago, and most people don’t drag their politics into the store with them when they’re looking for beer, duck boots or a blender.

Today Trump haters are trying to convince you to boycott products from L.L. Bean, KitchenAid, Gucci, Nike, Uber and many other corporate mainstays including Trident (for advertising on “Celebrity Apprentice”), Amazon (for selling Trump brand products) and Starbucks (for renting space inside some of Trump’s buildings). Targeting the progressive-minded Starbucks — whose CEO Howard Schultz was dubbed “the liberal Donald Trump” by The Atlantic — for being too Trump-friendly sounds like the kind of insane micro-distinction you’d encounter in 1937 Madrid, when hundreds of people were killed as one far-left group attacked another far-left group in the middle of a war against fascists.

Right-wing boycotters, of course, have also been busy. They staged a Twitter war against “Rogue One: A Star Wars Story,” after one of its writers blasted Trump on social media and pointedly said the Empire was “a white supremacist (human) organization.” (The movie only went on to gross a billion dollars.) They tried to take down Kellogg’s (whose stock price is higher than it was when it ran afoul of Trump fan site Breitbart.com) and Budweiser (over their multicultural Trump-trolling in a Super Bowl ad).

Some Trumpsters even started a #BoycottStarbucks movement of their own, inspired by the company’s promise it would hire 10,000 refugees in solidarity against Trump. Trump fans also agree that Amazon should be boycotted, because Amazon CEO Jeff Bezos owns The Washington Post, which has been mean to Trump. “You mess with Trump, your [sic] messing with the silent majority!” reads a petition calling for the boycott on Change.org.

When new boycotts and anti-boycotts are starting up every day, in the name of every cause, who can keep track of them all?

Then, last week, Nordstrom. The rich-lady department store, which was the target of an anti-Trump boycott as of last month (for carrying an Ivanka Trump line, even though Ivanka is probably the most liberal person Trump consults) is now getting hit with a pro-Trump boycott for dropping said line. A headline on Breitbart last week read, “Exclusive — Women Nationwide Cut Up Nordstrom’s Cards, Plan Boycotts After Political Decision to Drop Ivanka Trump Line.”

Hey, everybody, it’s time to switch sides on Nordstrom! And Amazon! And Starbucks! At least until the next 6 a.m. White House tweet gives us a little clarity about who’s on which side this second.

Armchair agitators may be giving pleasure to themselves but that’s really all they’re doing when they stage a boycott, a word that corporate America has long since learned to shrug off. If puns are the lowest form of wit, hashtags are the lowest form of social engagement.

The value of boycotts is, like the value of anything else, linked to scarcity. If the millions of Americans who hate Trump could focus their anger on one target, they might be effective. But when new boycotts and anti-boycotts are starting up every day, in the name of every cause, who can keep track of them all? The boycotters wind up limiting their influence to a handful of political monomaniacs, the kind of people who put up seven Facebook posts a day on the same topic.

Boycotters are fighting against a tide of human desire for products that are convenient, well-made or just simply delicious. At lunchtime every weekday in Midtown, you can see the lines out the door for Chick-fil-A, a fast-food chain whose CEO opposes gay marriage and which just last year earned a public denunciation from Mayor de Blasio, who said, “I’m certainly not going to patronize them, and I wouldn’t urge any other New Yorker to patronize them.” The franchise will soon open its fourth location in town, so even in this bastion of liberalism, mouth-watering poultry beats politics. Chickmate!