Donald Trump speaks during the final day of the Republican National Convention in Cleveland on Thursday. (Carolyn Kaster/Associated Press)

It was a grand old party at Quicken Loans Arena on Thursday night.

Delegates wore cowboy hats, straw hats, tricorn hats, stovepipe hats, cheesehead hats, evergreen hats and Uncle Sam hats. They bopped to the music of a seven-piece band and waved red, white and blue pompoms. There was a Donald Trump action figure here, a Donald Trump superhero cape there — and little sign of the NeverTrump dissension that marred the early days of the convention.

But as the hour grew late, just after Ivanka Trump declared brightly that “come Jan. 17 all things will be possible again,” the tone in the room took a dark turn.

Republican presidential nominee Donald Trump appeared on stage to the “Air Force One” movie theme and beneath 15-foot letters shouting TRUMP. For more than an hour, he shook his fists, chopped the air, stuck out his chin, bared his bottom teeth, paced behind the lectern, tugged on his lapels — and delivered the darkest piece of rhetoric spoken by a major political figure in modern American history.

“Our convention occurs at a moment of crisis for our nation,” he warned. “The attacks on our police, and the terrorism in our cities, threaten our very way of life.”

Trump’s portrait of America was dystopian and desperate:

“Violence in our streets.”

“Chaos in our communities.”

“We don’t have much time.”

“One international humiliation after another.”

“Forced to their knees.”

“Disasters unfolding.”

“In ruins.”

“Helpless to die at the hands of savage killers.”

“Worse than it has ever been.”

“Poverty and violence at home, war and destruction abroad.”

“Ignored, neglected and abandoned.”

“Communities crushed.”

“Horrible and unfair.”

“Corruption has reached a level like never, ever before.”

“Brutally executed.”

“Men, women and children viciously mowed down.”

“Families ripped apart.”

“Damage and devastation.”

“Such egregious crime.”

“This,” Trump concluded, “is the legacy of Hillary Clinton: death, destruction, terrorism and weakness.”

Morning in America it wasn’t. The delegates, so recently partying, were now booing and jeering at the horrors their candidate recited.

They booed more than 25 times during the speech. They booed, among other things: crime statistics, the debt, trade deals, illegal immigrants, Lyndon Johnson, NATO members and, above all, Clinton.

Trump invoked “mothers and fathers who have lost their children to violence spilling across our border.”

“Build a wall! Build a wall!” the delegates chanted.

“America is far less safe,” he said, “than when President Obama made the decision to put Hillary Clinton in charge of America’s foreign policy.”

“Lock her up! Lock her up!” they chanted. Trump nodded in approval at the controversial chant, then reconsidered. “Let’s defeat her in November,” he proposed.

Trump, by design, echoed the “law and order” theme from Richard Nixon’s 1968 acceptance speech in Miami. But this went far beyond Nixon, who in that speech took pains to answer “those who say that law and order is the code word for racism.”

Trump made no such qualification as he repeatedly employed that same racially loaded phrase. “When I take the oath of office next year, I will restore law and order to our country,” he said.

If there had been any lingering question, Thursday night’s acceptance speech made clear that there will be no “pivot” to the general election for Trump. His will be a turnout strategy, trying to mobilize the same aggrieved, older, white, less-educated, less well-off voters who flocked to him during the primaries.

But this isn’t 1968 — the year of the Rev. Martin Luther King Jr. and Robert F. Kennedy assassinations, Vietnam strife and race riots. True, crime has been rising the past couple of years — but from historically low levels. Even those in the hall didn’t seem to share Trump’s sense of an existential crisis.

“I’m not despairing,” said Ohio’s Jerry Hruby, who, at age 68, recalled 1968 being much worse. “People were just so unhappy.” I sampled delegates across the floor — from Missouri, Washington, Florida — and found none calling the current environment a crisis.

But Trump’s warnings of imminent catastrophe serve a purpose: In times of panic, the appeal of an authoritarian is greater. And Trump presented himself as the classic strongman.

“Beginning on Jan. 20th of 2017, safety will be restored,” he promised, later declaring that “I alone” can fix a broken system.

When a protester briefly interrupted his speech, he paused while she was hauled off, then remarked: “How great are our police!”

“I am your voice!” he assured those he had driven to despair. Though others only talk, he said, “I’m going to do it.”

“Yes, you will!” the delegates chanted.

There was a delay before the balloon-and-confetti drop at the end — and maybe they should have skipped it entirely. The rage and despair Trump generated hardly seemed to be cause for celebration.

Twitter: @Milbank

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