At the end of last month, President Trump declared that in November, the U.S. would honor Native American heritage. “This month, I encourage all of our citizens to learn about the rich history and culture of the Native American people,” he wrote.

On Monday, he stood in front of a portrait of President Andrew Jackson to thank World War II Navajo code talkers, using the opportunity to mock a senator who claimed Cherokee descent, by using a Powhatan name.

“I just want to thank you because you’re very, very special people,” Trump said, after a characteristically vague and nearly meaningless description of the role played by the men, who during World War II served in the Marines, using native languages as a code that the Japanese couldn’t break. Then he added: “You were here long before any of us were here, although we have a representative in Congress who, they say, was here a long time ago. They call her ‘Pocahontas.’”

That is, of course, Trump’s favorite nickname for Senator Elizabeth Warren of Massachusetts, who described herself as part Cherokee earlier in her career. Trump’s comment was astonishing. During an event honoring a specific group of Native American veterans of the Second World War, Trump suddenly veered into congratulating the men as exemplars of the all Native American peoples since time immemorial. He did so while standing in front of a portrait of Jackson, infamous for driving Native Americans out of the southeastern United States. And he used the ceremony to snipe at a political rival, delivering a personal insult while using an offensive nickname.

Native American groups have long criticized Trump for calling the senator Pocahontas. While he means to belittle Warren, they feel that it is also belittling to them. The nickname insults the original Pocahontas, a tragic figure who was kidnapped, and then later traveled to England with her husband John Rolfe, where she died; it conflates Pocahontas’s Powhatan heritage with other groups; and it is frequently used to mock Native Americans.

The president continues to use the nickname at this point not because he is ignorant of the offense he is causing but because he seeks to cause offense. According to a pool reporter, Trump’s comment was met with silence in the room. The men did not object, but they were hardly in a position to do so: They are veterans being honored by the commander in chief, and given that they are also seeking support for a code-talker museum, they have little incentive to criticize him. (Trump loves using captive audiences who can’t object to his offensive comments.)

Although the point of this particular insult may not be to offend Native Americans, it’s no surprise that Trump is indifferent to their complaints. The president has a long history of offensive comments about Native Americans. His October 31 statement about Native American Heritage Month is extremely fraught. “Beginning with the Pilgrims’ arrival at Plymouth Colony and continuing until the present day, Native American’s [sic] contributions are woven deeply into our Nation’s rich tapestry,” Trump wrote, a statement that makes no historical sense.

For one thing, English settlers interacted with Native Americans (yes, the Powhatans) at Jamestown 13 years before the Pilgrims’ arrival. Moreover, American history does not begin with the arrival of Europeans. Native Americans were contributing to what would become the United States long before Jamestown or Plymouth. Trump also wrote that “They helped early European settlers survive and thrive in a new land,” which reduces them to a Tonto-style supporting role and glosses over the violence committed against them by the same European settlers.

Minutes after Trump’s remarks, reporters at the White House briefing asked Press Secretary Sarah Sanders about what he’d said. Sanders rejected a characterization of the “Pocahontas” nickname as a racial slur. It is true that the name is not offensive per se, even if the specific use of it is. Trump has, however, endorsed the use of other anti-Native American slurs, saying that the name of the NFL’s Washington Redskins is “a positive” and that attempts to change it are “unnecessary political correctness.”

Sanders insisted that the real story was that Warren had claimed Native American heritage in order to advance her career. “I don’t understand why that isn’t constantly covered,” Sanders said. There are reasons why it’s not constantly covered, as Sanders knows: It’s been extensively covered. Warren’s claims of Native American heritage are not supported by any evidence, as Garance Franke-Ruta explained here in 2012. However, there’s also not any evidence that Warren benefited professionally from her claim of Cherokee blood.

The Trump administration should perhaps be careful about casting this particular stone in their glass house. While battling an attempt to establish Native American casinos that would have competed with his Atlantic City casinos, Trump said, “I think I might have more Indian blood than a lot of the so-called Indians that are trying to open up the reservations.” Even more damningly, Trump himself for years followed in his father’s footsteps by lying about his heritage in order to advance his career, saying his family came from Sweden rather than Germany. “Our country was at war with Germany,” he told The Boston Globe last year. “So being from Germany didn’t necessarily play so well for a period of time.”

Learn about rich Native American traditions, don’t lie about your heritage to advance your career—for the president, these are apparently matters of doing as he says, rather than as he does.