THE election in June saw the return of two-party politics. Labour and the Conservatives increased their share of the vote to 82%, from 65% in 2005. Yet look a little more closely at the two great parties that are currently holding their annual conferences—Labour in Brighton this week and the Conservatives in Manchester next—and you see a more complicated picture. Under Jeremy Corbyn, Labour is divided into two sub-parties: a moderate Social Democratic Party and a socialist Corbynite Party. The Conservatives are an uneasy coalition of Whigs and Tories.

The Corbynite Party was in charge in Brighton. Most of the trade unionists and activists who filled the hall were Corbynites, and Momentum, the molten core of Corbynism, helped to put on a parallel conference, “The World Transformed”. Tom Watson, officially Labour’s deputy leader and unofficially one of the commanders of the anti-Corbyn resistance movement, even treated the conference to a rendition of “Oh, Jeremy Corbyn”, the favourite chant of the faithful, in an abject admission of defeat. But the Social Democrats were nevertheless in evidence. Blairite MPs walked the seafront with rictus smiles. Labour First, a moderate pressure group, complained loudly that the left had stitched up the conference by denying speaking roles to centrists, most notably Sadiq Khan, the mayor of London (the organisers eventually relented). One moderate complained that he felt like a stranger in his own party. The sort of people who used to stand outside the hall handing out leaflets were now inside.

The Corbynites and Social Democrats differ fundamentally on the meaning of the election, in which Labour dramatically increased its vote-share but fell 64 seats short of a majority. Len McCluskey, the leader of the pro-Corbyn Unite union, gave vent to the Corbynite interpretation when he told the conference that he was tired of “whingers and whiners” who point out that Labour didn’t win. “I say we did win. We won the hearts and minds of millions of people, especially the young,” he insisted. Mr Corbyn told a fringe meeting that Labour would have won outright if the campaign had lasted another week. On this analysis, the task now is to work harder at selling Corbynism to the people.

The Social Democrats, meanwhile, believe that Labour lost a winnable election by backing a candidate and a set of policies that stand far outside the mainstream. The psephological evidence points in both directions. Mr Corbyn pulled off a remarkable feat by getting 40% of the vote. But his party is running neck-and-neck with the Conservatives in the polls, despite the fact that the government is doing its best to tear itself apart. A more centrist politician could be leading by double figures.

The Conservatives’ Manchester conference will be no less confusing. It will be shared by the Whigs, a cosmopolitan party that wants Britain to remain as close as possible to Europe, and the Tories, a nationalist party that worries about immigration and cultural change. The Whigs are mostly young and urban—David Cameron’s Notting Hill set writ large—while the Tories are older and rural. The Whigs think the Conservative Party must move with the times in order to survive, whereas the Tories think that moving with the times will mean surrendering everything they hold dear. Like the Corbynites, the Tories have numbers on their side. The Conservative Party enjoys impregnable majorities in places like Hampshire East, but has recently lost metropolitan beachheads such as Kensington and Battersea.

The Conservatives are just as divided over the meaning of the election as Labour. The Tories think that Theresa May’s strategy of advancing into culturally conservative working-class areas in the north was a brilliant idea badly executed. The party came close to winning a slew of Brexit-voting seats such as Bishop Auckland in north-east England. The Whigs agree that it was badly executed but think it was a foolish idea in the first place. By embracing social conservatism and little-England nationalism, the party alienated metropolitan Britain without breaking the working class’s tribal loyalty to Labour.

Conferences and after-parties

These divisions are not clear-cut. Some Conservative Brexiteers, such as Daniel Hannan, are radical Whig free-traders who liken the EU to the protectionist Corn Laws of the 1840s. Some of Labour’s chief Social Democrats, such as Mr Khan, have made a show of bending the knee to Mr Corbyn. The party conferences underline the fact that political parties are as much social organisms as political ones: an excuse to get drunk, have a good time and hang out with friends.

Yet Brexit is testing party managers’ skills to the limit. In government, the Conservatives cannot avoid making divisive decisions over Brexit. The party also contains a core of fanatics who have no intention of allowing the triumph of Brexit to be betrayed. Labour is also split. Mr Corbyn is cool on Europe partly because, as a socialist, he regards the EU as a constraint on policies such as nationalisation and partly because, as a party boss, he realises that many working-class Labour voters supported Brexit. By contrast, Labour’s Social Democrats are passionately pro-EU.

In Britain tribal loyalties usually trump ideological divisions. But occasionally ideological divisions prove too wide to manage, particularly when allied with economic interests. The Conservatives have split twice because of trade, first over the Corn Laws and then over imperial preference in the early 20th century. Brexit might yet prove to be just such a division. The Conservatives’ Whigs and Labour’s Social Democrats have far more in common with each other over Brexit (and much else) than they do with their parties’ radical wings. One of the big questions of the next year will be whether tribalism will prevail again—or whether the Whigs and Social Democrats can summon the courage to reach across the aisle and start voting as a block on the all-consuming question of Britain’s relationship with Europe.