IT WAS a winter night in 1854 when nine men broke into the building site of the Washington Monument, stole a slab of marble and—according to a later confession—heaved it into the Potomac river. The stone, which once belonged to the Temple of Concord in Rome, was a gift from Pope Pius IX. The attackers belonged to an anti-Catholic political movement, nicknamed “Know-Nothings” on account of their strict code of secrecy. Their movement considered Catholic immigrants a menace to the republic. At its peak, followers included dozens of congressmen, some governors and an ex-president. The Know-Nothings feared that the papal stone was a coded call to arms, sent to spark an immigrant uprising. Their vandalism helped to halt the monument’s construction for years. To this day a change in stone colour, part-way up the obelisk, betrays that nativist moment.

There is nothing secret about the nativist views of Donald Trump, a dyspeptic business tycoon running for the Republican presidential nomination. His finger-jabbing speeches about Mexican rapists and murderers, flowing across the border “like water”, and American jobs being shipped to China have taken him to the top of most polls. More dismaying, his apparent popularity has unmanned more conventional presidential rivals, only some of whom have chided him for his bigotry.

Mr Trump eventually managed to provoke a Republican backlash only after he attacked the war record of the Republican Party’s presidential nominee from 2008, Senator John McCain. Incensed after Mr McCain accused him of stirring up hard-right “crazies”, Mr Trump declared that the former Vietnam war pilot—who was shot down, imprisoned, tortured and declined to be released earlier than his fellow prisoners—was “not a hero”. “I like people that weren’t captured,” he later added, sarcastically. The tycoon and reality-TV star himself avoided service in Vietnam, in part thanks to a medical deferment due to bone spurs in his heel (in a press conference following the remarks about Mr McCain, he could not recall whether it was the right or the left one).

The Trump surge has been startling. After all, lots of conservatives growl about immigrants changing America, and shops full of cheap Chinese goods, without enjoying such success. Mr Trump is funding his campaign himself, which means he has no need to flatter donors. Is it this outsider status as a non-politician that marks him out? Or perhaps the unfiltered quality of his rage?

The Trump technique involves confiding in unhappy Americans that they are victims of a plot—and a plot, what is more, that could be easily thwarted. In his telling, scheming foreign governments have outwitted a soft political elite in Washington and preyed on America’s openness and generosity. He is tapping into a political tradition with deep roots. The Know-Nothings are only one example. The “America First” movement of the early 1940s accused decadent Europeans and well-connected Jews of conspiring to drag America into a new world war. In the 1960s the John Birch Society saw communist cunning at every turn.

To difficult questions Mr Trump offers appealingly simple solutions, starting with this most painful puzzle for conservatives: if America is the mightiest country in the world, how come it feels so weak? His answer goes beyond blaming Barack Obama and the Democrats. The fault, he insists, lies instead with the governing class in both parties, which has betrayed a great nation.

Mr Trump rails repeatedly against the “stupidity” of American leaders, who have allowed a scheming Mexican government to export its worst citizens across a porous border. He talks a lot about his dealmaking skills—“I went to the Wharton School of Business,” he told a rally in Arizona, “I’m like, a really smart person.” Armed with that business acumen, he promises to build a border wall and make Mexico pay for it. He suggests fining Mexico $100,000 every time its government “really intelligently” sends a migrant over. It is the same with China. The Chinese are ripping America off because “their leaders are much smarter”.

Wisdom from The Donald: What might we expect from a President Trump? A President Trump would bring jobs back by levying punitive taxes on firms that move factories overseas. America still has all the cards, he says soothingly. It is just that today’s American leaders don’t understand the game. The harshest blows to national morale are ascribed to elite naivety. Islamic radicals are growing rich from Iraqi oil, Mr Trump notes: this just shows that America should have seized Iraq’s oilfields. As for national security, a President Trump would hire a modern-day General MacArthur to run the army, and “nobody will be pushing us around.”

The leaning tower

Pundits disagree on what happens next. But Mr Trump’s fall will have to be steep and swift to keep him off the stage at the first Republican TV debate on August 6th, an important showcase reserved for the ten candidates doing best in national polls (converting a half-dozen other hopefuls into also-rans).

What is clear is that he will not win the Republican presidential nomination. Being horrible does have a political cost. Were he European, he could look forward to playing king-maker—channelling his spleen into a protest party capable of winning seats in parliament, and making life miserable for establishment rivals as they tried to build a governing coalition.

As it is, America’s two-party system offers him a bleaker choice: to stay on and heckle in the primaries or to play wrecker as a third-party candidate. Yet the Trump slump, when it happens, will not spell the end of the forces that have propelled him so far. Anti-politics rage is buffeting rich democracies across the world, and America is not immune to it.

Modern Washington is home to several gifts from the Mexican government, including a statue of a national hero, Benito Juárez, standing temptingly close to the Potomac. Until a mob hurls that into the river, look on Mr Trump and remember that candidates could be worse and, indeed, they sometimes have been.