The gravesite of Army Capt. Humayun Khan in Arlington National Cemetery in Virginia. (Mark Wilson/Getty Images)

Donald Trump betrays the betrayed.

In his acceptance speech at the Republican National Convention, Trump accurately and forcibly identified his core constituency and explained his candidacy:

“Every day I wake up determined to deliver for the people I have met all across this nation that have been ignored, neglected and abandoned. I have visited the laid-off factory workers and the communities crushed by our horrible and unfair trade deals. These are the forgotten men and women of our country. . . . People who work hard but no longer have a voice. I am your voice.”

And then, having mentioned the “forgotten men and women” of this country, he promptly forgot them. A week later, he was throwing a tantrum, tossing out of his playpen, which is the media, any notion that he recognizes any cause other than himself. He responded to Khizr Khan, who had spoken at the Democratic National Convention. He is the father of Humayun Khan, an Army captain who died in Iraq while trying to save the lives of other members of his unit.

Khizr Khan spoke as an American Muslim. He spoke as the father of a dead soldier, and he spoke with immense dignity. He rebuked Trump for what he has said about Muslims and, with powerful indignation, Khan said his son had sacrificed his life for the United States while Trump had “sacrificed nothing and no one.”

Convention speeches typically have their moment but soon become a blur, remembered only by the people who give them. Not the Khan speech. It had the rhetorical torque provided by grief — not just the loss of a son, but also the insults Trump had directed to Muslims in general. And as Khizr Khan spoke, his wife, Ghazala, stood by his side, eloquently silent.

Trump was asked by George Stephanopoulos of ABC News for his reaction. Trump implied that Ghazala Khan had said nothing because she was silenced by the traditions of Islam: “She had nothing to say. She probably — maybe she wasn’t allowed to have anything to say.” As Ghazala Khan later explained, she was too emotionally overwrought to speak.

Then Trump addressed the question of sacrifice. He claimed that he, too, had made sacrifices. “I think I’ve made a lot of sacrifices,” he said. “I work very, very hard. I’ve created thousands and thousands of jobs, tens of thousands of jobs.”

Taken together, his remarks had a gasp quality. Trump’s words had that sort of concussive effect — criticizing a Gold Star mother and a Gold Star father and likening their sacrifice to putting in some overtime at the office. Even after Trump’s belittlement of John McCain’s heroism, even after he mocked a New York Times reporter with a disability, he still has the capacity to shock. There are always new heights to how low he will go.

Trump’s appeal has largely been to working-class white males without college degrees — and some white women. You can understand why. Blue-collar workers are reversing time’s arrow, dying younger, much of it due to suicide and substance abuse. For many, their jobs are gone or going and so, therefore, is hope. The promise of America is that the son will live better than the father, the daughter better than the mother. But the fathers went off to jobs that no longer exist for the children. The fathers retired on pensions that now seem nostalgic fiction. Trump’s most ardent supporters are our version of the people of the old Depression-era song. They built a railroad. They made it run.

“Brother, can you spare a dime?”

It is clear from his success — and the current polling numbers — that millions of Americans believe that Trump is their voice. It is clear as well that they think he has an economic plan — kick out immigrants, get tough with China (and everyone else) and bring back jobs to the United States. Never mind that the plan lacks coherence or logic. To many, it sounds just swell.

Now, though, maybe even these people are repulsed by Trump’s comments on the Khans. His people wear the flag and sing the national anthem because, for some of them, being an American is about all they have left. Now they know Trump is not one of them. The Gold Star is sacred. It represents someone who died for our country. Donald Trump did not honor that. They always knew he was not a good man. Now they know he is not a good American.

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