WASHINGTON — President Trump challenged Democrats on Tuesday night to join him in overhauling immigration policies and in rebuilding the nation’s infrastructure in his first State of the Union address.

Speaking to a joint session of Congress, Mr. Trump hailed what he called the “extraordinary success” of his administration’s first year, and largely steered clear of the nationalist rhetoric, political attacks and confrontational tone that have been his calling cards both as a candidate and as a commander in chief.

“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,” Mr. Trump said to raucous applause from many Republicans, as Democratic leaders who have bitterly criticized his policies and messaging sat stone-faced in their seats.

“This, in fact, is our new American moment,” Mr. Trump said. “There has never been a better time to start living the American dream.”