The moment Donald Trump became US presidential

In an emotional moment surrounded by some of the best politicians in the country, real estate mogul Donald Trump finally managed to look presidential.

The US President's first speech to Congress was always going to be an important moment for Trump to put forward his vision for the country, and poor poll numbers ahead of the speech added to the pressure.

The White House's bungled rollout of the Trump's immigration and refugee ban, as well as questions hanging over the administration's links to Russia, saw Trump record historically low approval ratings for a new president.

Just 44 per cent of Americans approved of his job performance, according to an NBC News/Wall Street Journal survey, released ahead of his speech.

But Trump, who was not a politician before being elected as President, managed to pull off his first speech, delivered to Republicans and Democrats on Tuesday night (local time).

"A new chapter of American greatness is now beginning," he declared, after arriving to cheers and wild acclaim from members of the Republican-led House of Representatives and Senate.Hailing the emergence of a "new national pride", Trump pushed for tough immigration enforcement as the key to delivering jobs and security, even pointing to Australia's "merit-based" system.

"A new national pride is sweeping across our Nation. And a new surge of optimism is placing impossible dreams firmly within our grasp," he said.

Pressing his domestic agenda, Trump promised to provide "massive" tax relief for the American middle class and to repeal his predecessor's landmark Obamacare health reform, which expanded coverage to 20 million people.

But it was during one moment where Trump acknowledges Carryn Owens, the widow of a Navy Seal who was killed in a secret operation in Yemen, that appears to have provided a turning point for the President.

Owens was overcome with emotion as she received a standing ovation on behalf of her husband and the biggest applause of the night that lasted for more than two minutes.

Trump said that her husband, William "Ryan" Owens, died "a warrior and a hero battling against terrorism and securing our nation".

"Ryan's legacy is etched into eternity. Thank you," Trump said to Owens.

CNN commentator Van Jones, who has been one of Trump's most vocal critics, said that moment finally made Trump look presidential.

"He became president of the United States in that moment," Jones said.

"That thing he did just there, if he finds a way to do that over and over again he will be president for eight years."

It seems many others watching agreed.

A CNN/ORC poll found 57 per cent of those who watched the US President's first speech to Congress had a very positive reaction.

Nearly 70 per cent said they thought Trump's proposed policies would move the country in the right direction and that they felt more optimistic about the direction of the country.

Research fellow Dougal Robinson of Sydney University's United States Studies Centre said Trump's address was more optimistic than his inauguration speech 40 days ago.

"Trump's speech was optimistic and appealed to the sense of middle class optimism and the American dream," he said.

"He nevertheless identified a lot of enemies: illegal immigrants, drug cartels, gangs and Islamic terrorism."

Unlike the first speeches of his predecessors, Robinson said Trump did not make attempts to reach out to his political opponents.

He said the President had also set high expectations by promising that "everything can be fixed" and "every problem can be solved".

While Robinson expects the speech will be well received by his voter base, he believes Trump will struggle to gain Democrat support for his agenda.

"Few Democrats participated in the standing ovations and on most issues, congressional Democrats have little incentive to co-operate with President Trump."