We celebrated this week one of the purely American holidays, though Thanksgiving is replete with irony. A nation that treated it’s Native American benefactors with shameful cruelty uses their generosity to the Pilgrims as a role model.

Similarly, the history of the treatment of African Americans in this country is appalling. But millions of white Americans, if they gave it a moment’s thought, would give thanks for the remarkable courage, persistence and creativity of African Americans without whom this country would be a poorer, duller, lesser place.

It is easy at this moment to despair that the arc of history is not bending toward anything remotely resembling justice. Elections just concluded were tarnished by racist robocalls and state-sponsored efforts to suppress the minority vote. The President contributed his usual vile remarks, oblivious to the fact that refusing to be politically correct is often synonymous with being morally incorrect.

Trump, who with his father first made headlines for being prosecuted for discriminatory housing practices in Queens, dismissed the better educated, more experienced Stacy Abrams as being unqualified for the governorship of Georgia. It was soon to be stolen by a crude throwback to the days of Lester Maddox. Trump slandered Colin Kaepernick as unAmerican for exercising his First Amendment rights. He regularly brands exemplary public figures and public servants such as LeBron James and Maxine Waters as low I.Q.

This sort of talk was out of date when Al Campanis and Jimmy the Greek were permanently tarnished for expressing their casual bigotry on TV in the 1980s. The Greek said blacks were great athletes because they were bred for strength on the plantation, and Campanis suggested there were no black coaches, managers or quarterbacks because they “lacked the necessities.” That is, low I.Q.

And yet, African Americans have carried on in the face of an apparently never-ending ability to fail to see reality. We all share the same DNA. And since we all came out of Africa, ironically, we are all African American. In the face of persistent discrimination, African Americans keep right on excelling by overcoming hurdles they should not face.

As we watch the NFL this weekend, lo and behold, the playing fields are filled with black quarterbacks who apparently passed the I.Q. test — Russell Wilson, Cam Newton, Dak Prescott, rookie phenom Lamar Jackson, potential MVP Patrick Mahomes. And the coaching ranks have been enriched with minority contributors including two Super Bowl winners, Tony Dungy and Mike Tomlin.

The arts in America are unimaginable without African Americans. Their music is the soundtrack of all our lives and has been for over a century, — from Louis to the Duke, the Count, Ella, Miles, Nat, Ray up to the present, not to mention actors, dramatists, authors who have won Pulitzers, Tonys, and the Nobel Prize. They have made contributions in science and have filled CEO chairs in businesses including American Express, Xerox, Merck, and McDonalds without inheriting the business from the fathers.

African Americans also occupy leadership positions at important philanthropic institutions including the Carnegie Corporation, The Bill and Melinda Gates Foundation, the United Way and the Robert Wood Johnson Foundation. American food is also difficult to imagine if the contributions of African American influences were subtracted. Scottish cuisine, perhaps? And we can hardly forget that two of the most beloved, aspirational figures at present are African American women — Oprah and Michelle.

I was a young man when the Civil Rights generation of Martin Luther King Jr. asked the country to live up to its ideals, and white segregationists shamed themselves and our country by aiming fire hoses at peaceful protesters, siccing dogs on them, beating them, jailing them, murdering them, and yet their victims persisted. And still they persist.

A typical example of the uphill battle for respect concerns a National Museum of African American History and Culture, first proposed in 1915. Nothing was done until a new push was begun in 1970 after the Civil Rights era reforms. It still took until 1989 for Congress to entertain the idea, but another 15 years for the Smithsonian to sign on, Congress to actually vote yea in 2001, and a plan to emerge in 2003. Finally, in 2016 the museum opened.

At first a spot on the National Mall was refused because there was, supposedly, no more room. Congress also declined to fund the project fully, requiring private donors to bear much of the cost for the building and to help fund the creation of a collection. Foes surely assumed the notion would fail for lack of support. And yet the backers persisted, led by Rep. John Lewis, and in the first year three million visitors arrived to celebrate a place of honor in the nation’s capital.

Next year, fifty-three African Americans will serve in the House for the 116th Congress. Eight of nine new members were elected from majority white districts, which is a hopeful sign. Why should we not entrust the country to African American legislators? They have served with distinction on the Supreme Court, in leadership roles in the Armed Forces, and as the most recent President of the United States, a man who, compared to Trump, is as Shakespeare said, of the devolution from Hamlet’s father to his usurping uncle, “Hyperion to a satyr.”

So this Thanksgiving, perhaps all of us oblivious white Americans, part of a shrinking majority, ought to admit we owe an unacknowledged debt to our fellow Americans — Native, African, Hispanic, Asian, you name it — and give thanks for their presence and their part in making this a richer, more various country,

We also ought, at the very minimum, to speak up when any of us are dismissed, diminished, disrespected and denigrated. We are all Americans. Treating any of us with anything less than equal justice and respect has been wrong for almost 500 years and still is. Enough’s enough.