Washington (CNN) President Donald Trump sought to infuse his maiden State of the Union address Tuesday with an undercurrent of optimism, issuing a call for Democrats and Republicans to look past deep national divisions in order to do good by the American people.

Even as he worked to bridge growing national schisms, however, Trump didn't avoid the dark warnings about immigrants and nods to populist nationalism that have helped foment disunity over the past year.

Over the course of his 80-minute address -- one of the longest-running State of the Union speeches in history -- Trump heralded the economic successes of his first year in office, including a soaring stock market and low unemployment. He trumpeted the large package of tax cuts he signed into law last year and proclaimed that a regulatory rollback has allowed industries to thrive. And he staged several emotional moments with invited guests sitting in the first lady's box, including the parents of Otto Warmbier, who died after being returned to the United States by his North Korean captors.

The evening began with a precedent-breaking move by Melania Trump: instead of riding to the Capitol with her husband, the first lady arrived to the building early to meet privately with her invited guests.

And while Trump offered the traditional assessment of American strength -- "the state of our union is strong because our people are strong" -- Trump did little to acknowledge that his presidency has been decidedly nontraditional. He climbed the dais in the Capitol with one of the lowest approval ratings for any first-term president. His presidency continues to be clouded by investigations into his campaign's ties to Russia.

Trump sought to look past those facts and toward a future marked by unity and inclusion.

"This, in fact, is our new American moment," Trump said in his remarks, which rarely strayed from the prepared text loaded into his teleprompter. "There has never been a better time to start living the American dream."

Can optimism last?

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The moments of soaring optimism from the President stood in stark contrast to the message he often delivers on Twitter. It remained an open question how long the applause, which echoed in the House chamber, would linger, given the hard edges surrounding many of his policies.

Only a month after his first address to a joint session of Congress a year ago, Trump accused former President Barack Obama of wiretapping his conversations, a sign that behavior cannot be judged on one speech or one evening alone.

Tuesday's speech, laced with American stories of triumph and tragedy, did not mask the President's priorities or how he views issues like immigration. Even while pledging to extend "an open hand to work with members of both parties," Trump made clear his hard-line on immigration would take precedent over the "bill of love" that he mentioned earlier this month. And he devoted more time to MS-13 gang violence than he did to telling the stories of successful immigrants who have thrived in America.

"My duty, and the sacred duty of every elected official in this chamber, is to defend Americans -- to protect their safety, their families, their communities and their right to the American Dream," Trump said as he outlined a plan that would allow up to 1.8 million undocumented immigrants to remain in the country while funding a border wall, ending the visa lottery system and reforming family immigration rules.

But he was booed by Democrats when he used the fraught term "chain migration," and he laid bare the nationalist undertones of his policy by declaring "Americans are dreamers, too."

The remarks seemed unlikely to produce agreement between Republicans and Democrats, who will have to come together in some form to pass an immigration law. He didn't offer a pathway -- or even a head start -- toward solving the immigration impasse for the "Dreamers," which Democrats have insisted must be tied to a long-term government funding bill.

Trump also did not avoid oblique references to the divisive topics that have salted his first year in office, including the controversy over football players kneeling during the National Anthem.

Saluting a 12-year-old guest who spearheaded an effort to place flags on veterans' gravestones, Trump said the student's actions reminded all Americans of their "civic duty."

"Preston's reverence for those who have served our nation reminds us why we salute our flag, why we put our hands on our hearts for the pledge of allegiance, and why we proudly stand for the National Anthem," he said, to applause from Republican lawmakers in the crowd.

Highest-profile platform

A president's State of the Union is typically his highest-profile platform of the year, and viewership is generally higher in the first part of a presidency. But television ratings for the speech have steadily fallen over the decades, and Trump has shown a penchant for bypassing traditional communication channels in favor of social media.

If the State of the Union has assumed a reduced importance, however, there were no signs the White House took it any less seriously. For months, Trump fed handwritten notes with lines for the speech to his team of speechwriters, a White House official said.

In his speech, Trump called on lawmakers to approve a $1.5 trillion infrastructure package and touted his work on health care and in naming a new justice to the US Supreme Court.

Trump spoke most extensively about domestic affairs, but did reserve the final section of his address for foreign matters. He touted successes in battling back ISIS and again denounced the Iran nuclear deal. And he warned that North Korea could "very soon" be capable of threatening the US homeland with nuclear weapons.

"Past experience has taught us that complacency and concessions only invite aggression and provocation," Trump said of North Korea. "I will not repeat the mistakes of the past administrations that got us into this dangerous position."

Trump practiced delivering the address from the Map Room on Monday, the official said. Trump's predecessors also rehearsed their addresses from a mock podium and teleprompter set up in the White House basement room.

A team of speechwriters and top policy aides helped Trump craft his address, White House officials said. They included National Economic Council director Gary Cohn, national security adviser H.R. McMaster, senior policy adviser Stephen Miller and staff secretary Rob Porter.

Trump first reviewed a draft of his State of the Union address in December, and has made handwritten edits in recent days with black felt tip pens. In the last several weeks, Trump has workshopped ideas for the speech or edited certain sections while in the residence at night, handing over his changes to staffers the next day.

'United'

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Democrats selected Rep. Joe Kennedy III, a grandson of Robert F. Kennedy, to deliver the traditional response to the President's speech.

"Bullies may land a punch. They might leave a mark," the lawmaker said before a live audience gathered at a Fall River, Massachusetts, technical school. "But they have never, not once, in the history of our United States, managed to match the strength and spirit of a people united in defense of their future."

A number of other responses were also planned, including by Sen. Bernie Sanders, the independent Vermont senator who ran for President in 2016. A number of Democrats boycotted the speech.

Above the House floor, the administration's hosted guests in the first lady's box meant to illustrate policy objectives. This year the roster included a firefighter who helped battle blazes in California and the parents of teens killed by the MS-13 gang.

Melania Trump arrived at the Capitol separately from her husband so she could meet one-on-one with the invited guests. Presidents and first ladies typically travel to the speech together.

CNN's Jim Acosta, Kaitlan Collins, and Jeremy Diamond contributed to this report.