DONALD TRUMP’S presidency contains a puzzle. Opinions of the new president are remarkably clear-cut. Nine in ten of those who voted for him last November say they approve of his performance. Interviewed face-to-face, Trump supporters hail him for that rarest of political feats—doing in power just what he said he would do when campaigning. He has staged daily shows of action and resolve; scolding silver-haired CEOs to bring back jobs; signing executive orders to review and eventually repeal what he calls “job-killing” regulations, flanked by farmers or coal miners in hard hats. The heart of his first formal address to a joint session of Congress on February 28th was the line: “Above all else, we will keep our promises to the American people.”

Mr Trump’s opponents also seem sure that he is keeping his promises, albeit to their horror. More than nine in ten of Hillary Clinton voters say they disapprove of his presidency. Many predict his swift impeachment and demand “resistance” to all he does, an overwrought choice of word, implying that Democrats who work with him are treacherous collaborators. The resignation of Michael Flynn for lying about his contact with the Russian ambassador, and the forgetful testimony of Jeff Sessions, the attorney-general, in his confirmation hearing, have fed this sense that they are confronting a well-organised conspiracy.

For all that certainty in the country at large, the president remains a figure of sphinx-like mystery to those trying to work out what his government is actually doing. On the day of the big speech farmers and house-builders gathered in the White House to watch Mr Trump sign an executive order that he said paved the way for the elimination of a “very disruptive and horrible” rule, known as Waters of the United States (WOTUS), which aims to define which streams, small rivers and other waterways are subject to federal pollution controls. “It’s truly run amok,” said Mr Trump, suggesting at the signing that the rule has cost “hundreds of thousands” of jobs. In fact the rule was issued only in 2015 and has spent most of its short life suspended by court order. In a further touch of smoke and mirrors, Mr Trump’s order does not kill WOTUS but merely sends the issue back for review.

Or take immigration. Hours before his address to Congress, the president told TV anchors over lunch that “the time is right” for an immigration bill offering a pathway to legal status for foreigners who have committed no serious crimes—a proposal that his most fervent supporters would normally scorn as “amnesty”. But his speech made no mention of that approach, instead asserting: “We’ve defended the borders of other nations while leaving our own borders wide open, for anyone to cross”—though spending on border defences has more than doubled since 2001.

One of Mr Trump’s few tangible acts since taking office has been to issue instructions to federal agents that give them greater latitude to deport migrants encountered without papers, if they have been arrested for even minor crimes. Though he spoke soberly to Congress, Mr Trump harked back to his campaign rhetoric when he mentioned four guests in the House gallery whose relatives were “viciously” killed by illegal immigrants. He further announced the creation of a new government office tasked with reporting on crimes committed by immigrants. To be known as “Victims Of Immigration Crime Engagement” or VOICE, he declared that it will provide a platform for crime victims “who have been ignored by our media, and silenced by special interests.”

Though he offered some detail on this matter, Mr Trump left how he will shepherd his main plans through Congress, or pay for them, vague. He did not mention balancing the budget. He offered no guidance on fiscal questions that split Republicans down the middle, such as whether to support a border-adjustment tax on imports. The president came close to backing the replacement for Obamacare being proposed by Republican leaders in the House of Representatives. But he dodged the trade-offs involved, instead promising, regally, to “expand choice, increase access, lower costs and at the same time provide better health care.”

The puzzle, then, is why so many Americans are so sure that Mr Trump is keeping his promises. The solution lies in the president’s unusual relationship with his supporters. He was elected on grandiloquent pledges to “bring the jobs back” and build a “great wall” on the Mexican border that will stop people, drugs and crime. Those promises were really a commitment to be a champion for his supporters. Mr Trump can be hazy about what he plans to do because he is so clear about whom he represents: those he calls “forgotten” Americans, defined as hard-working, law-abiding heartland folk. And every time the news shows him signing some executive proclamation, the image carries almost as much messaging-power as a bill that took years to pass.

The man in the arena

If the president’s tone when addressing Congress felt more presidential than usual, it is because Mr Trump’s rhetoric expanded that in-group—those for whom he governs—to take in all Americans. Properly, he began his speech by condemning anti-Semitic attacks and an apparent hate crime in Kansas City, involving a white man accused of shooting dead an Indian-American engineer, while shouting “Get out of my country.” Later in the address, listing those ignored by elites, Mr Trump cited inner-city children from such diverse cities as Chicago, as well as the miners and factory workers of whom he usually speaks. All menaces can be beaten once America puts “its own citizens first”, he declared.

Broad-brush nationalism is better than the narrow tribalism Mr Trump often peddles. His great strength is his sense of his target audience, and of how those Americans see the world. But that is a strength more suited to campaigning than governing, and he takes power after making many impossible promises. Soon events will trigger hard choices. Mr Trump will have to lead, not just cheerlead. He has not yet shown he has that in him.