It’s been a decade to the day since Gordon Brown got caught calling Gillian Duffy a “bigoted woman” in a private conversation during the 2010 general election. Duffy, a retired grandmother who’d spent her life working with disabled children for the local council, had given the prime minister a piece of her mind whilst he was on the campaign trail in Rochdale. “My family have voted Labour all their lives,” she told him, “And now I’m absolutely ashamed of saying I’m Labour.” After some back-and-forth on crime, national debt and the difficulty of claiming benefits, Duffy interjected: “You can’t say anything about the immigrants … but all these eastern European what are coming in, where are they flocking from?”

Brown neither contradicted nor agreed with Duffy at the time, but after a polite end to the exchange, complained to one of his aides in the car: “That was a disaster – they should never have put me with that woman. Whose idea was that? Ridiculous.” Unfortunately for Brown, he was still wearing the microphone from his interview with Sky News (this detail no doubt heightened its shock value – one former advisor to Brown I spoke to says it was the first “hot mic” scandal of its kind in the UK). The comments were reported widely, and forced the PM to embark on a carnival of contrition around the nation’s broadcast studios.

According to The Mirror, Duffy single-handedly “changed the course of the [2010] election”. But tempting as it is to remember bigotgate as the moment that killed Brown’s chances of re-election, it’s worth remembering the lead-up to it.

After flirting with the idea of a snap election in 2007, Brown had been beset by external crises and party infighting. The financial crash sent the City into meltdown and triggered the biggest Treasury bailout in UK history. The parliamentary expenses scandal of 2009 decimated public trust in politicians, forcing Brown to apologise on their behalf.

The 2009 local and European elections were disastrous for Labour. Councils flipped to Conservative control, and Labour fell to third (behind Ukip and the Tories) in returning MEPs to Brussels. Framing those calamitous results were a series of high-profile cabinet resignations, including then-home secretary Jacqui Smith, communities secretary Hazel Blears, Europe minister Caroline Flint, and work and pensions secretary James Purnell. A few months later, The Sun withdrew its 12-year endorsement of Labour.

Haemorrhaging support in the press, the polls and his own party, Brown went into the 2010 election as the walking wounded. It’s not a huge surprise that his premiership didn’t survive the ballot box: it was on its last legs before Duffy ever drew breath to heckle the PM.

Yet even if bigotgate wasn’t the deciding factor in Brown’s fall, the themes it contained continue to plague Labour today. This encounter between an older, disaffected Labour voter and an embattled Labour leader exposed cracks in Labour’s base that would grow to a chasm by the end of Jeremy Corbyn’s leadership, and will be a significant obstacle in Keir Starmer’s pitch for No 10.

The episode raised an issue that has long troubled Labour – namely, immigration. For years, the party has attempted to pander to the anti-immigration sentiment widespread in the British public, yet this has almost always backfired. David Blunkett’s war against “bogus” asylum seekers served only to stoke fears of the country being overrun – fears on which the BNP capitalised. In 2007, Gordon Brown attempted to outflank Cameron on immigration by promising “British jobs for British workers” – yet this instead gave ammunition for a wildcat strike against foreign labour a year and a half later. No matter how reactionary the rhetoric or policies adopted by Labour, they still found themselves at odds with the portion of its electorate who could be tempted by the nationalism of right-wing parties.

What tripped up Brown on immigration was capitulating to anti-migrant sentiment in public but rebuking it in private. In a tantalising glimpse of what could have been, Brown’s former advisor recalled a focus group of swing voters put together by The Mirror. Their job was to give Brown a hard time on the issues that might trouble him in an election: pensions, taxes and, inevitably, immigration. One voter complained at length about no longer being able to recognise the country he grew up in “because there were too many people of colour on the streets”. According to the advisor who was present, Brown challenged the swing voter openly and explained uncompromisingly why he couldn’t accept that view. One can’t help but wonder what might have happened if Brown had been just as honest with Duffy.

BBC criticised for sharing Question Time audience member's anti-immigration rant

Brown’s exchange with Duffy was a pantomime of the ever-widening gap between Labour and its older, whiter and increasingly unreliable voter base outside of metropolitan centres. More than that, it confirmed a long-standing suspicion amongst the public that politicians were high-handed, distant and simply didn’t want to listen. For Labour, historically the party of workers’ struggle, ignoring the anger of ordinary voters came accompanied by a noxious whiff of hypocrisy.

“It always seemed to me to be ridiculously unfair how easy it was for Conservative politicians to walk away from those kinds of conversations,” says Brown’s ex-advisor, speaking to me on condition of anonymity. “There’s an inbuilt class element to it. It’s easier for David Cameron, or Boris Johnson hiding in a fridge, to say ‘Oh come on, this is a bit unseemly’, and have that be the end of it. But you can’t do that when you set yourself up as the party of the people.” As Matt Zarb-Cousin memorably put it, the Tories have the luxury of “playing politics on easy mode”. But it’s no bad thing that Labour is occasionally hamstrung by its principles, rather than free to ruthlessly pursue good PR.