To attack cultural appropriation as offensive or insensitive is to attack culture itself. And just as absurd. Everything from the food we eat to the Christmas many are about to celebrate is the result of cultural fusion, writes Chris Berg.

A spectre is haunting the planet: the spectre of cultural appropriation.

To appropriate symbols from cultures that are not one's own is apparently now disrespectful, insensitive and offensive.

A student body at the University of Ottawa has banned yoga classes as an example of "cultural genocide" and "Western supremacy". Student unions at the University of East Anglia have targeted Mexican sombreros for "discriminatory or stereotypical imagery".

At Oberlin College in Ohio, it is food that is problematic. The student dining hall is accused of modifying "traditional" Asian recipes "without respect". The "undercooked rice and lack of fresh fish" offered in sushi "is disrespectful". The Banh Mi sandwich, served on ciabatta rather than a baguette, is "uninformed", a "gross manipulation" of this "traditional" Vietnamese dish. And the General Tso's chicken dish is prepared with steamed chicken, rather than fried chicken - another disrespectful appropriation.

These complaints are apparently serious. They could just as well be satire. Because each of those named foods are themselves the result, not the victims, of cultural appropriation.

Sushi has an ancient history in Japan but what many people in Japan and the West now see as good sushi - with its rich slices of tuna and salmon - is the result of Japanese chefs adapting their traditional dish to the tastes of American GIs during post-war occupation.

The Banh Mi is a fusion dish of French baguette - brought to Vietnam through French colonialism in the nineteenth century - and Vietnamese flavours.

And General Tso's chicken? It dates back, at the earliest, to the 1950s, has nothing to do with the nineteenth century general Tso Tsung-t'ang, and only became famous when it was first served in a New York Chinese restaurant.

Sure, it's easy to mock a few uninformed university students. So let's continue.

The sombrero comes not from Mexico, but was brought from Europe by the Spanish - Don Quixote is often depicted with a flat-topped Spanish sombrero. The sombrero was then culturally appropriated by early American cowboys and evolved into their distinctive cowboy hat. For their part, the Spaniards got the sombrero from the Mongolians.

Modern yoga is so far from the ancient Indian tradition that it is better seen as a totally separate endeavour. The typical modern yoga fitness class draws on gymnastics, calisthenics and Indian wrestling. Its relationship to the fourth century Yoga Sutras of Patanjali is like the relationship between the cowboy hat and the Spanish sombrero: related but far enough apart to be considered substantively different.

Why is this important? Because the history of culture is the history of cultural appropriation. What we see as traditional national or ethnic cultures today are the just the current manifestation of a long evolutionary process. Traditional foods, religions, dress and practices are constantly changing as they are exposed to other cultures, picking up and integrating the most appealing or adaptable parts.

In her important 2013 book, Cuisine and Empire: Cooking in World History, the food historian Rachel Laudan documents the many ways so-called "national cuisines" are almost always an amalgam of foreign influences, incorporating plants, animals, techniques, spices and styles that have been pushed around the globe by politics and economics. There are no "authentic" cuisines, no "traditional" foods. Everything is fusion.

The same story could be told for language, architecture, dress, religion, music, art, literary culture and on and on and on.

So the issue here is not just that the criticism of cultural appropriation is historically illiterate. It's deeply ironic. The critics of cultural appropriation claim to be progressive. But they are in fact engaged in a deeply conservative project: one which first seeks to preserve in formaldehyde the content of an established culture and second tries prevent others from interacting with that culture.

Appropriating other cultural symbols is not empty, cynical role-playing, it is development. By appropriating we add meaning, creating complex new rituals and relationships.

Take, for instance, the most prominent example of cultural appropriation and evolution in the modern West: Christmas.

It is well understood that Christmas is an amalgam of Christian beliefs and Pagan rituals. The Christmas tree comes from Germany, Father Christmas from England, and Christmas carols from Roman-era Christian hymns. Most people would class candy canes as one of the secular icons of Christmas but they may have been meant to represent the shepherd's staff.

To observe a nativity scene (a first century AD stable in Bethlehem) next to a Christmas tree (an evergreen winter climate plant) is to see that there is a lot going with this apparently simple holiday.

Why is gift-giving part of the way we celebrate of the birth of Jesus Christ? Not solely because of the Three Wise Men. We might as well ask why Jewish families in the United States enjoy a plate of General Tso's chicken on December 25. Lots of reasons.

Cultural evolution is like that: a contradictory, rich, unstable mix of tradition and change. To attack cultural appropriation as offensive, or insensitive is to attack culture itself. And just as absurd.

Chris Berg is a senior fellow with the Institute of Public Affairs and author of Liberty, Equality & Democracy and Magna Carta: The Tax Revolt That Gave Us Liberty. Follow him on Twitter @chrisberg.