WINSTON CHURCHILL’S dictum—“We shape our buildings; thereafter they shape us”—may account for the distinctively cabalistic quality of British politics. The Palace of Westminster is a maze of sticky-carpeted little bars, poky wood-lined offices and forgotten meeting rooms up twisting staircases. It urges those who work in it to agglutinate and machinate. Thus tribes, gangs and factions drive politics in Britain to a greater extent than elsewhere. Recently three have produced national transformations: the Thatcherite cabal of the late 1970s, the New Labourites around Tony Blair in the 1990s and the anti-Europeans who have marked Conservative politics for the past three decades.

The third of these groups stands out, for it achieved its revolution without taking power. Inspired by Thatcher’s late, Eurosceptic turn and appalled by the disloyalty of the Europhile “grey men” who booted her out, they soared to prominence under John Major as he tried to secure support for the Maastricht treaty. “Bastards!” raged the then-prime minister of the rebels (later reflecting: “What I said was unforgivable. My only excuse is that it was true”). Back then they were relatively isolated. But over the long years of Labour government, the Conservative membership turned Eurosceptic; two “bastards”, Iain Duncan Smith and Michael Howard, served as leader; their successor, David Cameron, pandered to the gang. Having won Mr Cameron’s EU referendum, the bastards are supreme. Some are in the cabinet, others are breathing down their necks and a hard Brexit seems likely.

But if the old “awkward squad” is now the mainstream, what will take its place? Step forward, the Europhiles. The country’s nationalist direction since June 23rd has unified a new, younger band of continentally minded Tories. One is Anna Soubry, a former business minister who does not mince her words. “He looks like somebody has put their finger up his bottom and he really rather likes it,” she memorably told a television interviewer when asked about Nigel Farage of the Eurosceptic UK Independence Party. Nicky Morgan, a former education secretary, and Nick Herbert, an ex-policing minister, are her allies. George Osborne, a former chancellor and keener European than Mr Cameron ever was, is their shop steward. Ken Clarke, the rumpled, jazz-loving Europhile par excellence, serves as the resident greybeard.

There are differences within the gang. Mr Osborne favours a smaller state than the others. Only Mr Clarke doubts that the Brexit referendum should be treated as binding. But there are many more affinities. All are socially liberal. All question Theresa May’s tough line on immigration and her plans to create more academically selective state schools. All campaigned heart-and-soul for Britain to stay in the EU, question the prime minister’s rush to Brexit and want a “softer” break from the union, preserving the country’s membership of the single market. Sometimes they even sit together in the Commons: Mr Osborne has joined Ms Soubry on the bench farthest back from the prime minister, now dubbed the “naughty corner”.

Expect this group to gain influence once Mrs May triggers Article 50 in 2017, beginning the two-year countdown to Brexit. Already the prime minister is doing battle with Parliament. She wants to conduct the negotiations unscrutinised, but many MPs demur. A showdown will be the debate on the Great Repeal Bill, the legislation revoking the automatic transmission of European laws onto British statute books. This will create all sorts of opportunities for MPs to fiddle with the many volumes of European legislation reverting to Westminster’s control. Mrs May has a working majority of 15, which gives the soft Brexiteers (who number at least 20) the ability to intervene where they do not like the government’s line, just as their Eurosceptic predecessors so routinely and implacably did in the past. “They’ve certainly no reason not to fight just as dirty as the ‘bastards’ once did,” says Tim Bale, a historian of the Conservative Party.

Listen to the naughty corner

If they get it right, the soft Brexiteers could tilt Britain towards a more open, rational sort of Brexit. Yet they face all sorts of perils: irrelevance, disunity, submission. To avoid these, they could do worse than learn from the bastards. First, that means sticking together. For decades the hardline Eurosceptics have worked in unison, co-ordinating their campaigns and voting as a bloc to encourage party leaders to seek their favour. Second, the soft Brexiteers must build up an institutional network. The Tory right has had the Bruges Group, Better Off Out and Business for Britain; not to mention the editorial pages of the Daily Mail, Telegraph and Express. The Tory left has Open Britain, a pressure group patched together from the ashes of the Remain campaign, but little else.

Third, the soft Brexiteers need a limited list of incrementalist goals. The bastards rarely talked publicly about leaving the EU, but little by little edged the country towards that outcome. Applying that lesson, the Tory moderates might seek to keep Britain in the single market, curb the aggressive tone of Britain’s negotiators and rehabilitate Mr Osborne ahead of any future leadership race. Fourth and finally: they should reach out. The right always nurtured both sympathetic frontbenchers and the party’s base. Ambitious Tories, from Mr Cameron to prospective parliamentary candidates, have long had to convince the party of their Eurosceptic bona fides. So the Conservative left needs to create its own litmus test: aligning itself with friendly ministers (like Damian Green, the welfare secretary) and making its endorsement a valuable asset for those who want to make their way in the party.

Pro-market and socially liberal, the soft Brexiteers represent Britain’s truest instincts, as a mongrel nation created, whether it likes it or not, by grafters, merchants and immigrants. The Conservative Party has not always been a natural vessel for such people. But today it has a unique chance to represent them. It should do so with confidence.

Economist.com/blogs/bagehot