Accepting his party’s nomination, Donald Trump offered a dark and dystopian portrait of the country, presenting himself as a “law and order” leader who will put “America First”.

Domestic crime, the continuing threat of terror and failed leadership in Washington are combining to threaten the fabric of the land, Mr Trump suggested, insisting that Hillary Clinton, whom he labeled a “puppet” of corporations and the elite, is to blame for much of it.

“In this race for the White House I am the law and order candidate,” Mr Trump proclaimed, in a speech that also evoked familiar themes of restricting immigration and walling off Mexico.

This is “a moment of crisis for our nation,” the one-time reality TV host railed from the stage of the Quicken Loans Arena. “The attacks on our police, and the terrorism in our cities, threaten our very way of life. Any politician who does not grasp this danger is not fit to lead our country.”

“Americans watching this address tonight have seen the recent images of violence in our streets and the chaos in our communities,” Mr Trump added, delivering surely the most important speech of his short political career, with tens of millions watching at home.

“I have a message for all of you: the crime and violence that today afflicts our nation will soon, and I mean very soon, come to an end. Beginning on January 20th 2017, safety will be restored,” he said, vowing to win the race for the White House. Among other pledges he made during the night: “I am going to make our country rich again.”

Donald Trump is 'colour-blind and gender neutral,' his daughter told the crowd in Cleveland ((Getty Images))

As he strode onto the stage after an introduction by his daughter, Ivanka, he was greeted by sustained cheers and rolling chants of his name, his supporters reveling in a moment that even they, and certainly much of the country and world, surely never thought they would see.When he was done the rafters released a cloudburst of red, white and blue balloons.

It was an address laced with some his familiar boasting of his stunning conquest of the Republican Party. But it was designed also to emphasise the perceived qualities that attracted primary voters to him in the first place: his promise to be a strong leader with a disdain for political correctness.

“It is finally time for a straightforward assessment of the state of our nation,” the New Yorker said in his oratorical style that is more cloddish than soaring. “I will present the facts plainly and honestly. We cannot afford to be so politically correct anymore.”

He depicted a country also weakened by misbegotten adventurism abroad, a criticism that could have been leveled as much at George W. Bush of his own party as at President Barack Obama.

“Iraq is in chaos. Iran is on the path to nuclear weapons. Syria is engulfed in a civil war and a refugee crisis that now threatens the West. After 15 years of wars in the Middle East, after trillions of dollars spent and thousands of lives lost, the situation is worse than it has ever been before.” He went on: “This is the legacy of Hillary Clinton: death, destruction and weakness”.

Choruses of ‘Lock her up!’, which erupted on every night of the convention, made their return when Mr Trump recalled how President Obama had chosen to put Ms Clinton in charge of foreign affairs. Rather than acknowledging them, he restricted himself to: “Let’s defeat her in November.”

His ‘America First’ twist on foreign policy won’t calm allies unnerved by remarks made in an interview this week that under his leadership the US wouldn’t necessarily help other members of Nato if they were invaded by Russia if they weren’t pulling their financial weight in the Alliance.

Protestor decrying Trump's comments on Nato (David Usborne)

“The most important difference between our plan and that of our opponents, is that our plan will put America First. Americanism, not globalism, will be our credo,” Mr Trump asserted.

“As long as we are led by politicians who will not put 'America First,' then we can be assured that other nations will not treat America with respect, the respect that we deserve,” he boomed. “The American people will come first once again.”

“We are going to defeat the barbarians of Isis and we are going to beat them fast,” Mr Trump said touching on international terrorism. “Only weeks ago, in Orlando, Florida, 49 wonderful Americans were savagely murdered by an Islamic terrorist. This time, the terrorist targeted our LGBT community, no good, we are going to stop it.”

Then Mr Trump promised further to do “everything in my power” to protect the lesbian, gay and transgender community, “from the violence and oppression of a hateful foreign ideology”. When the room reacted warmly to a topic not normally emphasized by their party, Mr Trump, veering off script, responded: “As a Republican it is so nice to hear you cheering for what I just said”.

On all fronts, including trade and economic policy, Mr Trump cast himself as the champion of the ignored, promising to stand up for "the forgotten men and women of our country, people who work hard but no longer have a voice.” Than he said baldly: “I am your voice.”

“I have joined the political arena so that the powerful can no longer beat up on people that cannot defend themselves. Nobody knows the system better than me, which is why I alone can fix it. I have seen firsthand how the system is rigged against our citizens.”

“Middle-income Americans and businesses will experience profound relief, and taxes will be greatly simplified for everyone. America is one of the highest-taxed nations in the world,” if he becomes president, he offered. “Reducing taxes will cause new companies and new jobs to come roaring back into our country.”

He repeated his campaign promises to block new free trade deals and possibly renegotiate existing ones, another area of concern for America’s partners. Those treaties, he said, “strip this country of its jobs and strips us of our wealth”.

Populism was weaved through the address. “Every action I take, I will ask myself: does this make life better for young Americans in Baltimore, Chicago, Detroit, Ferguson who have as much of a right to live out their dreams as any other child America."

“There can be no prosperity without law and order,” Mr Trump offered. As he broached the issue of immigration, the hall broke into instant chants of “Build the wall!

It was the passages on immigration that had been arguably the most eagerly awaited. “We must immediately suspend immigration from any nation that has been compromised by terrorism until such time as proven vetting mechanisms have been put in place. We don’t want them in our country,” he said, adding: “I only want to admit individuals into our country who will support our values and love our people.”

While Mr Trump did not speak specifically of barring Muslims from entering the country - a proposal that caused uproar when he it first - he did reiterate his pledge to build the wall. “We are going to build a great border wall to stop illegal immigration, to stop the gangs and the violence, and to stop the drugs from pouring into our communities,” he said.

He closed his audition to nation with a message less of doom and disaster and more of hope. .