What word comes to mind when you see the name Donald Trump? For some people, it might be “anger,” since he provokes it and stokes it. For others, it might be “ignorance,” since he knows so little and, like many unburdened by knowledge, is untroubled by facts. Some might say “fear,” since it would take some scary police tactics to push 11 million people over the border to Mexico. For me, none of those words suffice. I’d choose “betrayal.”

It is the word that comes to mind almost on a nightly basis when I see some Trump surrogate defend his position on one of the cable news shows. How can you? I want to ask. Do you believe that the government should apply a religious test to let people into this country? Christians? Yes. Jews? Sure. Buddhists, Hindus and Zoroastrians, step this way. Muslims? Not so fast.

Do the people who support Trump realize that they are betraying not merely Muslims but the principles that America stands for? We don’t apply religious tests to anything. In that way, we are different than some other countries. In that way, we are better.

It is the same with what Trump said about Mexicans being “rapists.” It was an ugly, bigoted thing to say — and, of course, wrong as hell. So when some Trump supporter breezes right by that statement on the way to whoopee support of restricted trade or allowing Japan and South Korea to get nuclear weapons, I feel betrayed. I can abide policy differences but I cannot abide indifference to bigotry. And neither should any of Trump’s supporters.

I felt that same, awful feeling of betrayal when Trump mocked a physically disabled reporter for The New York Times. Did Trump’s people notice? Did they care? Aren’t Americans supposed to stick up for one another?

How about the way he insulted John McCain? The man was tortured and Trump belittled it. The man was in solitary for two years, and Trump belittled it. I thought Americans would never stand for that. This was John McCain, son of an admiral, grandson of an admiral, United States senator. How much redder can a man’s blood be?

Donald Trump has taught me to fear my fellow American. I don’t mean the occasional yahoo who turns a Trump rally into a hate fest. I mean the ones who do nothing. Who are silent. Who look the other way. If you had told me a year ago that a hateful brat would be the presidential nominee of a major political party, I would have scoffed. Someone who denigrates women? Not possible. Someone who insults Mexicans? No way. Someone who mocks the physically disabled? Not in America. Not in my America.

When I see these Trump supporters on television — the commentators, the Politician’s Puttanesca (a dish to poison the body politic) — I have to wonder where they would draw the line. Nowhere. They want to win. They want to beat Hillary Clinton, a calling so imperative that sheer morality must give way. Muslims and Mexicans are merely collateral damage in a war that must be fought. What about blacks or Jews? Not yet.

Maybe the talking heads on TV would draw the line at some mild version of fascism, but would the American people do the same? Here, I must hesitate. The easy yes of yesteryear has given way to awful doubt. Trump could win. He could become president, commander in chief, ruler of the Justice Department and head of the IRS. In other words, the American people could elect someone who has not the slightest appreciation for the Constitution or American tradition. When Trump insisted that he could compel a military officer to obey an illegal order, I heard the echo of jackboots on cobblestone.

In America, no one is required to follow an illegal order. It does no good to argue that Trump is just doing a shtick, that he means little of what he says, that he is all swagger and bluff. Trouble is, his supporters do not see him that way. They take him at his word.

History nags. It admonishes. American exceptionalism is a phrase that refers to the past, not necessarily the future. Nothing is guaranteed. I’d like to think that Americans really are exceptional, that we have an exceptional faith in democracy and the rule of law. I now have some doubt. I always knew who Trump was. It’s the American people who have come as a surprise.

Richard Cohen is a columnist for The Washington Post. His email address is: cohenr@washpost.com.