Updated at 11:16 p.m. ETPresident Trump sought to strike a unifying tone with his first State of the Union address, but some of his rhetoric on immigration and his promise to put "America First" was clearly aimed at his base.As a March 5 deadline approaches for Congress to come up with a legislative implementation of the the Deferred Action for Childhood Arrivals (DACA) program, Trump outlined the ways he wants to roll back legal immigration as a compromise for giving a path to citizenship for up to an estimated 1.8 million undocumented immigrants brought here as children.But his rhetoric elicited boos from Democrats in the chamber as the president alluded to the common term of "dreamers" for those immigrants."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. "Because Americans are dreamers too."Trump also pointed out guests in the chamber whose children had allegedly been killed by the MS-13 gang, and called on Congress "to finally close the deadly loopholes that have allowed MS-13, and other criminals, to break into our country.""For decades, open borders have allowed drugs and gangs to pour into our most vulnerable communities. They've allowed millions of low-wage workers to compete for jobs and wages against the poorest Americans. Most tragically, they have caused the loss of many innocent lives," Trump said.And throughout, Trump highlighted his "America First" agenda. For example, in terms of legal immigration Trump wants to end the visa lottery system and limit family reunification policies to spouses and children only."We are proud that we do more than any other country to help the needy, the struggling, and the underprivileged all over the world. But as president of the United States, my highest loyalty, my greatest compassion, my constant concern is for America's children, America's struggling workers, and America's forgotten communities," Trump said.Trump began the address with a unifying, uplifting tone, talking about how Americans have responded to tragedies the country has faced over the past year, from natural disasters to mass shootings."Over the last year, the world has seen what we always knew: that no people on Earth are so fearless, or daring, or determined as Americans. If there is a mountain, we climb it. If there's a frontier, we cross it. If there's a challenge, we tame it. If there is an opportunity, we seize it," Trump said. "So let's begin tonight by recognizing that the state of our union is strong because our people are strong. And together, we are building a safe, strong and proud America.""But through it all, we have seen the beauty of America's soul, and the steel in America's spine. Each test has forged new american heroes to remind us who we are, and show us what we can be," the president continued.He also pointed out House Majority Whip Steve Scalise, R-La., calling him the "legend from Louisiana," who survived a life-threatening shooting at a congressional baseball practice last June."In the aftermath of that terrible shooting, we came together not as Republicans or Democrats, but as representatives of the people. But it is not enough to come together only in times of tragedy," Trump said. "Tonight, I call upon all of us to set aside our differences, to seek out common ground, and to summon the unity we need to deliver for the people. This is really the key. These are the people we were elected to serve."Trump's first year has been marked by record low approval ratings, and a majority of Americans said in a recent NPR/PBS NewsHour/Marist poll that Trump has done more to divide the country than to unite it.Despite his comments about the need for national unity, the president also forcefully highlighted one of his more divisive comments early in his remarks Tuesday.Trump alluded to his call to fire NFL players who kneel during the national anthem. Many saw those remarks at the time as racially-charged, given that most of the athletes taking a knee as a silent protest were black players seeking to protest police brutality particularly affecting African-American communities. But Trump's efforts last year to spotlight the kneeling protests have been a popular play with his conservative base.Pointing out a 12-year-old boy, Preston Sharp, who was attending the speech as Trump's guest who took it upon himself to put flags on veterans' graves, Trump used the opportunity to call for more adherence to "our civic duty as Americans.""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," Trump said.Trump played up his economic success and highlight the GOP tax plan passed last month, the signature achievement of his first year in office."Small business confidence is at an all-time high. The stock market has smashed one record after another, gaining $8 trillion dollars and more in value in just this short period of time," Trump said.The president, however, did not mention that just hours before he was set to deliver his speech the stock market closed by taking a triple-digit hit."Our massive tax cuts provide tremendous relief for the middle class and small business, to lower tax rates for hard-working Americans," Trump said in touting the new tax law. The president also promised that this year "will be the last time you will ever file under the old and very broken system. And millions of Americans will have more take-home pay, starting next month. A lot more."Trump also called for a $1.5 trillion package "to rebuild our crumbling infrastructure" in partnership with state and local governments, "and, where appropriate, tapping into private sector investment.""We built the Empire State Building in just one year. Isn't it a disgrace that it can now take 10 years just to get a minor permit approved for the building of a simple road?" Trump queried. "I am asking both parties to come together to give us the safe, fast, reliable, and modern infrastructure that our economy needs and our people deserve."Rep. Joe Kennedy III, D-Mass., delivered the official Democratic response to Trump's speech and seized on the division in the country as he spoke after the president."It would be easy to dismiss the past year as chaos. Partisanship. Politics. But it's far bigger than that. This administration isn't just targeting the laws that protect us — they are targeting the very idea that we are all worthy of protection," Kennedy said. Copyright 2018 NPR. To see more, visit http://www.npr.org/.