Donald Trump needed to give the speech of his life. He did that, and much more. He laid out an inspiring American Manifesto for our troubled times.

And he did it his way.

Not surprisingly, from start to finish, it is muscular and bold, leavened only by appeals to racial harmony and pledges of compassion for all. It offers a prominent nod to Bernie Sanders’ supporters in a bid to get some to jump the Democratic ship.

Most important, it keeps faith with his campaign themes of putting forgotten Americans first. In contrasting his view with his opponent’s, the Republican nominee put it this way: “Americanism, not globalism, will be our credo.”

And “I am your voice.”

And then this: “There can be no prosperity without law and order.”

On paper, the speech is powerful, and it was delivered with all the might Trump could muster. Passionate and occasionally strident, then mellow and playful, he revealed a full Trump Doctrine that weaves together what has often seemed random threads and instincts into a more coherent vision.

He would unleash America’s energy production, use trade deals to help blue-collar workers and fix the broken immigration system so that cheap labor doesn’t undercut wages and overwhelm our social safety net.

He would ensure public safety, rebuild the military and destroy global terrorism. And he forcefully and repeatedly cemented the image of the GOP as the pro-police party, a strong contrast with Democrats, who are recklessly becoming the anti-police party.

Trump laid out such a huge undertaking, sweeping in its goals and potential impacts, that achieving even half of it would lead to an economic revival and end the nation’s crisis of confidence. If he focused on just what he outlined last night, and he should, Trump would be a very busy man every minute for the next four years.

In that context, he addressed the inevitable sense that little change can come in a nation so polarized and gridlocked by reminding the raucous convention that he wasn’t even supposed to be standing before them. And in a line that captured his remarkable attack on the political status quo, he said, “The politicians have talked about this for years, but I’m going to do it.”

There is, at this point, no reason to believe he doesn’t mean every word of it. Whatever his past habits and lifestyle, whatever caricature he has been reduced to, the seriousness of his purpose is no longer in doubt. He is a man on a mission.

As befits an acceptance speech, the promises flowed like water, yet the important things stand out. This one, from his prepared remarks, was especially powerful: “On January 20th of 2017, the day after I take the oath of office, Americans will finally wake up in a country where the laws of the United States are enforced.”

He was blistering on Hillary Clinton, saying her legacy as secretary of state was “death, destruction, terrorism and weakness.” Nor did he spare President Obama, accusing him of using “the pulpit of the presidency to divide us by race and color” and saying he “has made America a more dangerous environment for everyone.”

Trump then added: “This administration has failed America’s inner cities. It’s failed them on education. It’s failed them on jobs. It’s failed them on crime. It’s failed them at every level.”

The stirring speech saved what had been a mediocre convention, with sloppy mistakes leading to distracting controversies and fueling fears that Trump and his team still are not ready for prime time. Delegates were not so much divided as dispirited over the prospect that the party would once again lose a very winnable race.

Especially with the well-oiled and well-funded Clinton machine revving up its engines with attack ads and with her message amplified by the left-wing media echo chamber, Trumpsters suddenly faced an enthusiasm gap. Rows of empty seats in the Quicken Loans Arena seemed symbolic of sagging hopes.

A turning point might have come Wednesday night, during the booing of rival Ted Cruz for refusing to endorse Trump. What started with restlessness from the New York delegation quickly spread, and by the time he slinked off the stage, Cruz suffered a stunning and unanimous rebuke.

That rare moment of genuine unity, followed by Mike Pence’s workmanlike acceptance speech as the VP nominee, set the stage for the finale. Indeed, no matter what had come before, it was always going to be up to Trump himself. He’s the nominee and the whole venture rises or falls on his performance.

It now rises. He delivered a stemwinder for the ages.

If he wins, and can deliver on his vision, remember this speech. Like Ronald Reagan’s in 1976, Trump’s 2016 address could mark the start of a desperately needed American revival. As he said near the end, “America is back.”

Imagine that — and pray he is right.