Sen. Elizabeth Warren speaks on Oct. 18.  (Michael Reynolds/European Press Agency-EFE)

On Tuesday, the White House proclaimed November as Native American Heritage Month. On Friday, President Trump took jab at a political foe using a name that many Native Americans consider a slur.

He's invoked Pocahontas before in jabbing Sen. Elizabeth Warren (D-Mass.).

Warren's claims of Cherokee and Delaware Indian heritage first attracted national attention during her 2012 Senate run. While she had family stories, she did not have any documentation of her Native American ancestry to prove it, even though Cherokee groups demanded it. Her opponent, the Republican incumbent Scott Brown, claimed Warren used family lore to get an unfair advantage in getting hired to coveted faculty jobs at Harvard Law School and University of Pennsylvania Law School.

During remarks at the National Rifle Association conference in Atlanta on April 28, President Trump said that the NRA will be "swamped" with candidates next election. "It may be Pocahontas, remember that," he said, referring to the insult he used for Elizabeth Warren during the 2016 presidential campaign. (The Washington Post)

The Washington Post Fact Checker found no support for Brown's claims:

We found no proof that she ever marked a form to tell the schools about her heritage, nor any public evidence that the universities knew about her lineage before hiring her. Still, we found that Warren’s relying on family lore rather than official documentation to make an ethnic claim raised serious concerns about Warren’s judgment.

Trump capitalized on Warren's inability to verify her story with documentation, particularly after Warren questioned his honesty.

Then and again this week, Trump found himself on the receiving end of criticism for his apparent inability to push back on Warren without causing offense.

Rep. Raul Grijalva (D-Ariz.) said the president's words suggest that he is out of touch with Native Americans.

Indian Country columnist Ruth Hopkins said Trump is mocking Native American women by invoking Pocahontas, a member of an Algonquian tribe encountered by English captain John Smith on an expedition in Virginia.

And the chief ethics lawyer for former president George W. Bush called out President Trump for his words.

Author and radio host Roben Farzad said someone in the business community would be fired for Trump's actions.

Trump's comment is the latest in a series of recent slights some Native Americans have felt from the Trump administration.

Trump did not mention Native Americans in his Columbus Day proclamation and instead had a Columbus Day sale to allow customers supportive of the navigator's voyage to purchase the “Make America Great Again” merchandise of their choice for a discounted price.

Native Americans protested his administration's approval of the Dakota Access pipeline, which some argue violates treaties that indigenous groups living on the Standing Rock Indian Reservation signed with the federal government in the 1800s.

And despite all the proclamations to tackle the opioid epidemic, Native American activists say there seems to be no real attempt to target efforts in Native American communities despite their faring the worst of all minority groups, according to the Centers for Disease Control and Prevention.

Trump is not known to back down from criticism that he believes is rooted in political correctness, but maybe he will consider the previous words of a fellow Republican, Rep. Tom Cole (R-Okla.).

“He needs to quit using language like that,” Cole said in June 2016, after a previous attack. “It’s pejorative , and you know, there’s plenty of things that he can disagree with Elizabeth Warren over, this is not something that should, in my opinion, ever enter the conversation. . . . It’s neither appropriate personally toward her, and frankly, it offends a much larger group of people. So, I wish he would avoid that.”

Presumptive Republican nominee Donald Trump took aim at Sen. Elizabeth Warren (D-Mass.) at a rally in Tampa, Fla., on June 11. He called Warren "Pocahontas," a jab at her claim that she is of Native American descent. (Reuters)