Thanksgiving is coming – a time to participate in the great American tradition of maligning and abusing our ancestors. Last year, Seattle public school administrators warned teachers that “Thanksgiving can be a particularly difficult time for many of our Native students.” Accordingly, teachers were advised to consult a list of 11 Thanksgiving “myths.”

No. 11 read as follows: “Myth: Thanksgiving is a happy time. Fact: For many Indian people, ‘Thanksgiving’ is a time of mourning, of remembering how a gift of generosity was rewarded by theft of land and seed corn, extermination of many from disease and gun, and near total destruction of many more from forced assimilation. As currently celebrated in this country, ‘Thanksgiving’ is a bitter reminder of 500 years of betrayal returned for friendship.”

In his new book, “The 10 Big Lies About America” film critic and radio talk show host Michael Medved recalls the Seattle episode, as well as many other examples of self-flagellation that now characterize many of our national observances.

Columbus Day? The start of a vicious subjugation. A Denver Columbus Day parade was marred last year by protesters who threw fake blood and dismembered dolls along the parade route.

Plymouth Rock? Weren’t the Native Americans here first after all?

The 400th anniversary of the landing at Jamestown was renamed from celebration to “commemoration” in 2007 because “so many facets of Jamestown’s history are not cause for celebration.”

Medved, a passionate but not blind patriot, argues that our kids and the rest of us are being fed a tendentious history that wildly exaggerates the offenses of European settlers. The notion that “America Was Founded on Genocide Against Native Americans” cannot withstand scrutiny.

Like racism, genocide is a word that has lost its meaning through promiscuous overuse. Medved reminds us that the international “Genocide Convention” defines genocide as an act or acts “committed with intent to destroy, in whole or in part, a national, ethnic, racial, or religious group as such.” In the clash of civilizations between European settlers and Native Americans, millions died. But the overwhelming majority of those deaths were attributable to diseases carried involuntarily by Europeans and spread to natives who had no natural immunities to these pathogens. That is a tragedy, but not a crime.

There were terrible injustices and massacres committed by Europeans against Native Americans and some running the other way as well. The more technologically advanced civilization prevailed – which is the usual course in human affairs. But the current fashion to distort that history into something like a war crime is, to say the least, overstated.

The Thanksgiving story is a strange one to protest. It is recalled, every year, as a time when newly arrived Europeans and Native Americans cooperated and learned from one another and then joined together for a festive meal to celebrate their joint harvest.

This week, millions of schoolchildren will don tall paper hats and Indian fringes and feathers. They will recall the peaceful start of the not always peaceful history of the greatest nation on earth. And so they should – without guilt or shame.

Happy Thanksgiving.