Want proof that the liberal social-democratic society works?

Look to Denmark, the country that routinely leads the world in happiness surveys. It’s also notable for having the highest taxes on Earth, plus a comfy social safety net: Child care is mostly free, as is public school and even private school, and you can stay on unemployment benefits for a long time. Everyone is on an equal footing, both income-wise and socially: Go to a party and you wouldn’t be surprised to see a TV star talking to a roofer.

The combination of massive taxes and benefits for the unsuccessful means top and bottom get shaved off: Pretty much everyone is proudly middle class. Danes belong to more civic associations and clubs than anyone else; they love performing in large groups. At Christmas they do wacky things like hold hands and run around the house together, singing festive songs. They’re a real-life Whoville.

In the American liberal compass, the needle is always pointing to places like Denmark. Everything they most fervently hope for here has already happened there.

So: Why does no one seem particularly interested in visiting Denmark? (“Honey, on our European trip, I want to see Tuscany, Paris, Berlin and . . . Jutland!”) Visitors say Danes are joyless to be around. Denmark suffers from high rates of alcoholism. In its use of antidepressants it ranks fourth in the world. (Its fellow Nordics the Icelanders are in front by a wide margin.) Some 5 percent of Danish men have had sex with an animal. Denmark’s productivity is in decline, its workers put in only 28 hours a week, and everybody you meet seems to have a government job. Oh, and as The Telegraph put it, it’s “the cancer capital of the world.”

So how happy can these drunk, depressed, lazy, tumor-ridden, pig-bonking bureaucrats really be?

The Jante Law

Let’s look a little closer, suggests Michael Booth, a Brit who has lived in Denmark for many years, in his new book, “The Almost Nearly Perfect People: Behind the Myth of the Scandinavian Utopia” (Picador).

Those sky-high happiness surveys, it turns out, are mostly bunk. Asking people “Are you happy?” means different things in different cultures. In Japan, for instance, answering “Yes” seems like boasting, Booth points out. Whereas in Denmark, it’s considered “shameful to be unhappy,” newspaper editor Anne Knudsen says in the book.

Moreover, there is a group of people that believes the Danes are lying when they say they’re the happiest people on the planet. This group is known as “Danes.”

“Over the years I have asked many Danes about these happiness surveys — whether they really believe that they are the global happiness champions — and I have yet to meet a single one of them who seriously believes it’s true,” Booth writes. “They tend to approach the subject of their much-vaunted happiness like the victims of a practical joke waiting to discover who the perpetrator is.”

Danes are well aware of their worldwide reputation for being the happiest little Legos in the box. Answering “No” would be as unthinkable as honking in traffic in Copenhagen. When the author tried this (once), he was scolded by his bewildered Danish passenger: “What if they know you?” Booth was asked.

That was a big clue: At a party, the author joked, it typically takes about eight minutes for people to discover someone they know in common. Denmark is a land of 5.3 million homogeneous people. Everyone talks the same, everyone looks the same, everyone thinks the same.

This is universally considered a feature — a glorious source of national pride in the land of humblebrag. Any rebels will be made to conform; tall poppies will be chopped down to average.

The country’s business leaders are automatically suspect because of the national obsession with averageness: Shipping tycoon Maersk McKinney Moller, the richest man in the country before his death in 2012, avoided the national shame of being a billionaire by being almost absurdly hoi polloi. He climbed stairs to his office every day, attended meetings until well into his 90s and brown-bagged his lunch.

An American woman told Booth how, when she excitedly mentioned at a dinner party that her kid was first in his class at school, she was met with icy silence.

One of the most country’s most widely known quirks is a satirist’s crafting of what’s still known as the Jante Law — the Ten Commandments of Buzzkill. “You shall not believe that you are someone,” goes one. “You shall not believe that you are as good as we are,” is another. Others included “You shall not believe that you are going to amount to anything,” “You shall not believe that you are more important than we are” and “You shall not laugh at us.”

Richard Wilkinson, an author and professor who published a book arguing for the superiority of egalitarian cultures, told Booth, “Hunter-gatherer societies — which are similar to prehistoric societies — are highly egalitarian. And if someone starts to take on a more domineering position, they get ridiculed or teased or ostracized. These are what’s called counter-dominance strategies, and they maintain the greater equality.”

So Danes operate on caveman principles — if you find it, share it, or be shunned. Once your date with Daisy the Sheep is over, you’d better make sure your friends get a turn. (Bestiality has traditionally been legal in Denmark, though a move to ban it is under way. Until recently, several “bestiality brothels” advertised their services in newspapers, generally charging clients $85 to $170 for what can only be termed a roll in the hay.)

They need a drink

The flip side of the famous “social cohesion” is that outsiders are unwelcome. Xenophobic remarks are common. At gatherings, the spirit of “hygge” — loosely translated as cozy — prevails. It’s considered uncouth to try to steer the conversation toward anything anyone might conceivably disagree about. This is why even the Danes describe Danes as boring.

In addition to paying enormous taxes — the total bill is 58 percent to 72 percent of income — Danes have to pay more for just about everything. Books are a luxury item. Their equivalent of the George Washington Bridge costs $45 to cross. Health care is free — which means you pay in time instead of money. Services are distributed only after endless stays in waiting rooms. (The author brought his son to an E.R. complaining of a foreign substance that had temporarily blinded him in one eye and was turned away, told he had to make an appointment.) Pharmacies are a state-run monopoly, which means getting an aspirin is like a trip to the DMV.

Other Scandinavian countries (Booth defines the term broadly, to include Nordic brethren Iceland and Finland in addition to Denmark, Sweden and Norway) raise other questions about how perfect the nearly perfect people really are. Iceland’s famous economic boom turned out to be one of history’s most notorious real estate bubbles. A common saying in Denmark about Icelanders: They wear shoes that are too big for them, and they keep tripping over the shoelaces.

The success of the Norwegians — the Beverly Hillbillies of Europe — can’t be imitated. Previously a peasant nation, the country now has more wealth than it can spend: Colossal offshore oil deposits spawned a sovereign wealth fund that pays for everything.

Finland, which tops the charts in many surveys (they’re the least corrupt people on Earth, its per-capita income is the highest in Western Europe and Helsinki often tops polls of the best cities), is also a leader in categories like alcoholism, murder (highest rate in Western Europe), suicide and antidepressant usage.

Their leading filmmaker, Aki Kaurismaki, makes features so “unremittingly morose they made [Ingmar] Bergman look like Mr. Bean,” reports Booth.

Finnish etiquette demands little in the way of conversation (the men, especially, speak as if being charged by the syllable) but much in the way of alcohol abuse. It’s considered poor form to leave the party when there is anything left in a bottle. Although their overall alcohol consumption is near the European average, they binge-drink more than almost any other country on the continent. Booze-related disease is the leading cause of death for Finnish men, and second for women.

The suicide rate is 50 percent higher than in the US and more than double the UK rate. Party guests, even at upscale gatherings, report that, around 11:30 at night, things often take a fighty turn.

It turns out that the “warrior gene” — actually the enzyme monoamine oxidase A, which is linked to impulsive behavior, violence and alcoholism — is especially prevalent in Finland. “Dark” doesn’t just describe winter in the Arctic suburbs, it applies to the Finnish character.

Big bowl of oatmeal

Macho isn’t a problem in Sweden. Dubbed the least masculine country on Earth by anthropologist Geert Hofstede, it’s the place where male soldiers are issued hairnets instead of being made to cut their hair.

But Scandinavian cohesion may not work in conjunction with massive immigration: Almost one-third of the Swedish population was born elsewhere. Immigration is associated in the Swedish mind with welfare (housing projects full of people on the dole) and with high crime rates (these newcomers being more than four times as likely to commit murder). Islamist gangs control some of the housing projects. Friction between “ethnic Swedes” and the immigrants is growing.

Welfare states work best among a homogeneous people, and the kind of diversity and mistrust we have between groups in America means we could never reach a broad consensus on Nordic levels of social spending.

Anyway, Sweden thought better of liberal economics too: When its welfare state became unsustainable (something savvy Danes are just starting to say), it went on a privatization spree and cut government spending from 67 percent of GDP to less than half. In the wake of the global financial crisis, it chose austerity, eliminating its budget deficit (it now runs a slight surplus).

As for its supposedly sweet-natured national persona, in a poll in which Swedes were asked to describe themselves, the adjectives that led the pack were “envious, stiff, industrious, nature-loving, quiet, honest, dishonest and xenophobic.” In last place were these words: “masculine,” “sexy” and “artistic.”

Scandinavia, as a wag in The Economist once put it, is a great place to be born — but only if you are average. The dead-on satire of Scandinavian mores “Together” is a 2000 movie by Sweden’s Lukas Moodysson set in a multi-family commune in 1975, when the groovy Social Democratic ideal was utterly unquestioned in Sweden.

In the film’s signature scene, a sensitive, apron-wearing man tells his niece and nephew as he is making breakfast, “You could say that we are like porridge. First we’re like small oat flakes — small, dry, fragile, alone. But then we’re cooked with the other oat flakes and become soft. We join so that one flake can’t be told apart from another. We’re almost dissolved. Together we become a big porridge that’s warm, tasty, and nutritious and yes, quite beautiful, too. So we are no longer small and isolated but we have become warm, soft and joined together. Part of something bigger than ourselves. Sometimes life feels like an enormous porridge, don’t you think?”

Then he spoons a great glutinous glob of tasteless starch onto the poor kids’ plates. That’s Scandinavia for you, folks: Bland, wholesome, individual-erasing mush. But, hey, at least we’re all united in being slowly digested by the system.