Smothered by political ideology, America’s great museums are failing their mission as the protectors of our shared human heritage.

I should know: I’ve spent the last year immersed in a study of the world-renowned museums of New York City, after Heterodox Academy’s Segal Center for Academic Pluralism awarded me a fellowship to explore museum exhibits for viewpoint diversity and accuracy of information.

Tragically, I found that museums have become just another arena for pushing political agendas, especially those supporting the postmodern ideology that identity — race, gender, nationality and class — is more important than truth.

At the American Museum of Natural History’s Northwest Coast Hall, indigenous superstitious beliefs that harm can come from artifacts intended for shamans are treated with complete seriousness.

The exhibit comes with a medical-style warning label: “CAUTION: This display case contains items used in the practices of traditional Tlingit doctors. Some people may wish to avoid this area, as Tlingit tradition holds that such belongings contain powerful spirits.”

Similar warnings are found behind the scenes in curation rooms used by museum staffers and visiting scholars.

There, pregnant and menstruating women are currently told to stay away from “objects of power” that contain human hair, and everyone is cautioned to not even look at the bird-bone whistles that can summon “supernatural beings.”

When a natural-history museum blurs fact and fiction, it has failed at both its educational and its scientific mission. Signs warning of dangerous spirits are the antithesis of science.

Now, however, nearly all of the museum’s Native American exhibits have been shuttered completely due to the Biden administration’s “Indigenous Knowledge Mandate” and regulatory changes to the Native American Graves Protection and Repatriation Act.

These regulations require tribal permissions for display of any Native American artifacts.

When the museum’s Native American exhibits reopen — perhaps years from now — they’ll contain far fewer items for visitors to study. More superstitions will be represented as facts, and we’ll surely see many more warning signs.

It’s not just Native American artifacts that have been removed: The museum has also decided to no longer exhibit any human remains after AMNH president Sean Decatur argued that they were not “essential” to the “goals and narrative of the exhibition.”

But no cast or reproduction can show the intricate detail of real human bones — features that could spark the imagination of future forensic anthropologists or budding doctors.

Removing human remains has also resulted in the loss of artifacts from the museum’s Aztec exhibit, including a musical instrument created from a human shin bone.

Such items are important teaching tools to illustrate that cultures around the world and in different times have a variety of ways to treat the deceased — ways considered respectful in that time and place — and burial is not necessarily the norm.

Overall, I found an odd mix of presentism, ethnocentrism and, frankly, squeamishness in the museum’s shifting approach.

Meanwhile, art museums are increasingly restructuring exhibits around identity politics — leading to confusing displays with no natural organization or flow.

At the Metropolitan Museum of Art, the exhibit “Look Again: European Paintings 1300–1800” focuses on “class, gender, race, and religion,” which in practice means that geographic locations and artists are jumbled throughout the halls.

Furthermore, exhibit curators redrew the border of Europe to include some of Asia and Africa — apparently a clumsy attempt to retrospectively insert diversity into the past where none existed.

Similarly, “The African Origin of Civilization” exhibit paired ancient Egyptian works with far more recent African pieces, to show how Egypt influenced the rest of Africa and vice versa.

Yet anthropologists have debunked such theories, leading curators to point to “similarities” in depictions of universal concepts found in all cultures, such as the relationship between mother and child.

Perhaps no piece of art in the Met exemplifies its focus on identity politics more than the display of “Delaware Water Gap,” a panoramic landscape painted by George Inness in 1861.

It’s a large-scale view of an area on the border of Pennsylvania and New Jersey that shows grazing cows and the contrasting modernity of a steam train. The serene scene is crowned with a rainbow — perhaps evoking the calm after a storm.

But the Met’s “Native Perspective” description of the painting invokes “genocide,” the “capitalism” that threatened native people’s “very existence” and the current “chaos and destruction of climate change.”

Experiencing these relentless pieties led me to conclude that our museums — where children’s curiosity is piqued, where research collections are used to understand the world around us and where young and old alike can travel the world without a passport — are in their final days.      

Elizabeth Weiss is a professor emeritus of anthropology at San José State University and author of “On the Warpath: My Battles with Indians, Pretendians, and Woke Warriors.“