As a percentage of its population, Iowa sent more troops to fight in the Civil War than any other state.

Iowans fought on the side of the Union against the Confederate South.

Abraham Lincoln, the president of the United States and the commander in chief of Union forces, was the first Republican president.

So it seems odd (to me, at least) that a Republican congressman from Iowa would display a Confederate flag on his desk. But that’s what Rep. Steve King did as recently as 2016. (He removed it only after it was revealed that a cop killer had waved a Confederate flag at an Iowa high school football game.)

I’m not one of those people who think everyone who displays a Confederate flag is necessarily a racist or a bigot.

But I usually reserve the benefit of the doubt for actual Southerners who are nodding to tradition or nostalgia.

If there’s one thing King has not earned it’s the benefit of the doubt.

Even accounting for an IQ that seems to be in conflict with the idea that white people are superior, the man understands what he’s up to.

In an interview with the New York Times published Thursday, King asked: “White nationalist, white supremacist, Western civilization — how did that language become offensive? Why did I sit in classes teaching me about the merits of our history and our civilization?”

The obvious answer is because he needed an education — and still does. At the 2016 Republican National Convention, King responded to the suggestion that the GOP needs to appeal to Americans other than old white people: “I’d ask you to go back through history and figure out, where are these contributions that have been made by these other categories of people that you’re talking about, where did any other subgroup of people contribute more to civilization?”

Contrary to the prattle of white nationalists and supremacists (and, interestingly, various left-wing theorists and black nationalists such as Louis Farrakhan), Western civilization is not synonymous with whiteness.

Many of the people King would count as white today were not considered white by various giants of American white nationalism and white supremacy. Czechs, Hungarians, Poles, Italians, Greeks et al. weren’t “whites” at the beginning of the 20th century, when the Steve Kings of that era were terrified of non-white immigrants.

In 1911, the joint congressional Immigration Commission completed a 41-volume report that included the Dictionary of Races or Peoples, a pseudoscientific grab bag containing “a motley compendium of ethnic stereotypes, skin complexion, head shape, and other hardy perennials of the race science literature,” according to Princeton historian Thomas Leonard in his vital book “Illiberal Reformers.”

Bohemians had heavy brains. Southern Italians were too “excitable” and “impulsive” to adapt to organized society. Slavs were overly prone to “periods of besotted drunkenness” and “unexpected cruelty.” Germans from the Tyrol region were too broad-headed to be of desirable stock.

In fairness, “white” wasn’t a term of art back then, so white supremacists were actually Aryan or Nordic or English (not Irish!) supremacists. But you get the point.

Then there’s the notion that non-whites haven’t made worthy contributions to civilization. Leave aside that by not counting Italians (sorry, Galileo and Da Vinci!), East Europeans (sucks for you, Copernicus!) or Jews (Einstein? Good riddance) as white, you’re bequeathing many of the glories of civilization to non-whites. But even with the most expansive definition of “white” possible, how do we account for the fact that Chinese, Ottoman and Arab societies were leaps and bounds ahead of Europe for centuries?

The Chinese invented the compass, paper, movable type, mechanical clocks, iron smelting and countless other innovations when “white” Europe was a barbaric backwater. And let’s not forget that Christianity is a cultural import from that great melting pot that was the Middle East.

One is reminded of Benjamin Disraeli’s famous retort to an Irish Catholic parliamentarian’s anti-Semitic attack on his heritage: “Yes, I am a Jew, and when the ancestors of the right honorable gentleman were brutal savages in an unknown island, mine were priests in the temple of Solomon.”

But this is the wrong way to respond to King’s bigotry. Among the best ideas and ideals of Western, Christian and, most importantly, American civilization is that we are supposed to judge people on their individual merits, not keep score based on their ancestry.

This vision was central to the creation of the Republican Party, which is why it’s so dismaying that Rep. King calls himself one.

Goldberg’s latest book, “Suicide of the West,” is now available.