Melania Trump, the First Lady of the United States, will view her husband’s State of the Union address this evening in the company of parents whose daughters were murdered by members of MS-13, the Salvadoran-American criminal gang. It seems a strange elevation in status for MS-13. If the state of the union in the most powerful and wealthiest nation on Earth is actually strong, what does a street gang have to do with anything? The choice gives some insight into the nature of the Trump era, one year in, with his party in unified control of government in Washington but his Presidency historically unpopular. During the State of the Union, the President gets to describe his agenda but also set the national scene. Trump is giving significance to an immigrant street gang. He is in search of an enemy.

There are plenty of ways to measure the difference between the Trump who took office and the one who now presides, but one is in the collapse of his ambition. At his Inaugural, a year ago, Trump was grandiose and dark in his rhetoric, taking as his theme a scene of “American carnage” that he insisted was sweeping the land. (“That was some weird shit,” President George W. Bush was reported to have said while sitting in the audience, as the speech ended.) The new President insisted that élites in Washington had strangled the nation (“Politicians prospered, but the jobs left and the factories closed”); that globalization had threatened the country’s prosperity (“We’ve made other countries rich while the wealth, strength, and confidence of our own country has disappeared over the horizon”); and that his election would free the country from their grip. “Now,” the new President promised, “arrives the hour of action.”

READ Comments and analysis from New Yorker writers on the 2018 State of the Union address.

Trump’s account was so ambitious that it seemed to envision his election as something much bigger than democratic politics—a sharp break with the past. “From this day forward, a new vision will govern our land,” the President said then. Part of the foreboding among Trump’s opponents that accompanied his Inauguration depended on the fear that Trump might be right—that a nativist political party might weave protectionism, kleptocracy, and reactionary politics of gender and race in order to win majorities. The atmosphere last winter around Trump and his chief strategist, Steve Bannon, was apprehensive. They represented a dark, racialized idea of the American future. They had also won the election. Perhaps they had seen something that the rest of us missed.

If they had, it looks faint now, and so does the imprint of the Trump revolution. Policy has never much interested Trump or his White House, and so the slogan “America First” has become something more abstract than an agenda—a way of talking, a chyron on Fox News. The Administration’s initial travel bans were drafted so amateurishly that judges across the country quickly ruled them unconstitutional. During its tortured effort to repeal Obamacare, the White House made few specific proposals and then blamed members of Congress for the debacle. The G.O.P. tax cut was drawn up by Republicans in Congress with little guidance from the White House. And during the recent debate over Dreamers the question of what policy, exactly, the President wanted shifted so frequently that it helped fuel a government shutdown. In these episodes of this very chaotic year, the idea that the President might augur some broader social tumult and change has faded; he has collapsed back into the factional world of Washington politics, and his preferences now match those of the institutional Republican Party, which he had started out denouncing.

The speech tonight, the President’s surrogates have said, will aim for a different tone—a bit brighter, its optimism leaning on the economy, now in its ninth year of a crawling, unspectacular recovery. Yesterday, recently returned from Davos, Trump was said to be editing and practicing the speech in the White House Map Room; today, his schedule is clear, too. But the meaningful matter, as it was at the Inauguration, is not how the President talks but what he will do. Trump will reportedly detail his bargaining position on immigration (in which he would accede to permanent legal protections for the Dreamers in exchange for a dramatic expansion of funding for border security and sharp reductions in legal immigration) and unveil the infrastructure project that is meant to be his Administration’s major legislative ambition in 2018. Both of these are gestures at bipartisanship, but the details of his immigration position have made Democrats livid, and the meagre federal funding proposed for his infrastructure plan has left them cold. The opposition has been winning elections, and the chance to argue with Trump is so enticing that the State of the Union will be followed by five separate Democratic addresses in opposition.

The President’s challenge is to unify the country when he has become a factional figure, with most of the population obviously unified against him. The mood around the President has been bitter this week. Trump, on the flight to Davos, was said to have raged about the ongoing investigation of his ties to Russia. Shortly after he returned to the U.S., the news was that Andrew McCabe, the F.B.I. deputy director, had stepped down, following months of attacks from the President, which began in May, when Trump told McCabe to ask his wife what it felt like to be a political "loser." By this morning, the political news was of more moderate Republicans in Congress who have chosen to retire rather than seek reëlection, and the President’s eldest son was retweeting conspiracy Web sites suggesting that an anti-Trump F.B.I. plot had been uncovered. A year ago, much of the country was tensely imagining what was possible if America’s government was unified behind an aspiring strongman. Now it is measuring what it has to fear if the President is profoundly, perhaps fatally, weak.