Angela Rayner’s exit proves it. Unless Starmer is able to meet this moment, Reform is on the path to power | John Harris

The prime minister increasingly looks like a man next to a burning house, offering to buy a new bookcase and rug

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One hundred and twenty miles from Westminster, it felt like I had arrived at the perfect place to understand the meaning of Angela Rayner’s exit from the government: Reform UK’s brief conference, a giddy and surreal gathering of about 10,000 people in a hangar-like box on the edgelands of Birmingham.

News of her resignation broke a couple of hours into the event’s first day, and the symbolism was glaring. Among midday pints, onstage pyrotechnics and a huge stand advertising the wonders of investing in gold, a party led by those bumptious public schoolboys Nigel Farage and Richard Tice was suddenly rejoicing in the departure of British politics’ most prominent working-class woman. The news, moreover, only boosted an atmosphere of energy and optimism, laced with a delighted surprise at what might be the UK’s defining political fact. We all know it: this new party has a tiny handful of MPs, no meaningful policy platform and a worldview that constantly blurs into conspiracy theory, but Reform UK is on course to either form or lead the next British government.