It’s tempting to suggest The Donald picked the perfect venue to showcase his quixotic presidential campaign – the State Fair of Oklahoma.

After all, a carnival barker would naturally migrate to the Midway, wouldn’t he?

Sarcasm aside, Trump and some of his fellow 2016 Republican travelers – hello, Ben Carson – could learn something important by taking stock of the faces in the State Fair crowd.

Oklahoma, like America itself, is a wonderful melting pot of races, cultures and religions, most living in harmony and respecting differences.

It’s a truth that too often is lost in today’s increasingly strident political discourse – when bombast trumps reason (pun intended) and Trump, Carson and Co. dismiss pushback against their ugly stereotypes as political correctness run amok.

Oklahomans should well remember the vitriol aimed at almost anyone thought to be of Middle East descent after the 1995 Oklahoma City bombing.

At the outset, speculation focused on foreign terrorism, including reports of a pickup truck with Middle Eastern-looking men speeding from the scene. Oft-dubious news coverage drove many of our neighbors with Middle East roots into the shadows temporarily. Redneckism flourished.

Even when it was determined homegrown terrorists were responsible for the attack, the suspicions didn’t die completely, fanned by xenophobes and conspiracy theorists.

It’s a sad day when the likes of Trump and Carson ignore the lessons of history – how unchecked demagoguery and stereotyping can become a cancer on society, destroying so many innocents.

Trump never repudiated his demonization of Mexican immigrants as mostly criminals. The billionaire also lacked the courage to push back against a supporter’s anti-Muslim comments, a stark contrast to Sen. John McCain, a real war hero, in his presidential bid seven years ago.

Carson, a retired neurosurgeon who surged recently in the polls, declared he does not believe a Muslim should be president, asserting, “We have an American culture and we have an American Constitution and anybody who’s going to occupy our White House should be living in a pattern that is consistent with our constitution and our culture.”

Really? It’s bad enough he doesn’t understand the Constitution forbids a religious test. It’s even worse he doesn’t seem to grasp the notion that a president is president of all Americans – not just those whose religious worldviews he shares.

Most appalling of all, too few GOP presidential candidates seem willing to speak against such bigotry – the sort of nonsensical talk that automatically would have disqualified a candidate a generation ago.

Now it’s up to clear-eyed folks like those gathering at the state Capitol earlier this week, in advance of Trump’s visit, to denounce the hate-speech and warn of the consequences to our pluralistic society of such rhetoric.

This isn’t about political correctness. It’s about bigotry. And calling out those who would stoke such hate.

“Bigotry is not natural, it is learned,” wrote Adam Soltani, executive director of the Council on American-Islamic Relations’ Oklahoma Chapter, and the Rev. William Tabbernee, executive director of the Oklahoma Conference of Churches, in a joint statement. “And it begins with the propagation of information that is patently untrue, as well as insensitive. Such untruths are dangerous and damaging to the fabric that holds us together as a nation of religious freedom. History has shown repeatedly that hateful words too often lead to violence.”

It’s bad enough we, on the state level, elect bigots like state Rep. John Bennett, R-Sallisaw, who periodically uses his office to attack Islam and fan suspicion about its adherents. Now Republican primary voters give serious consideration to candidates that are either guided by such hateful principles or are willing to exploit them for ultra-rightwing votes.

Somewhere Joe McCarthy must be smiling.

Arnold Hamilton is editor of The Oklahoma Observer,