Ten years after Brexit, the U.K. marks a lost decade

On June 23, 2016, the Brexit referendum unleashed a populist tide that rewrote the rules of Western politics.Ten years later, a diminished and fractured United Kingdom is preparing for its seventh prime minister — still haunted by the future it was promised.Why it matters: Keir Starmer was elected as a competent, level-headed antidote to 14 years of Conservative rule — a period consumed by austerity, ideological warfare and the chaos of leaving the European Union.His resignation on Monday, less than two years after a historic Labour landslide, reveals Britain's chronic instability has outgrown partisan explanation.State of play: For many Western leaders, the U.K. is the ultimate cautionary tale — a live experiment in modern populism, unfolding inside one of the world's oldest and wealthiest democracies.Brexit began with utopian promises of an unshackled Global Britain that could curb immigration, slash red tape and take back control of its borders and budget.Instead, a succession of Conservative prime ministers plunged the country into deeper dysfunction: Theresa May was broken by the Brexit negotiations, Boris Johnson by scandal, Liz Truss by market panic, and Rishi Sunak by electoral humiliation.Today, Britain remains marooned in a low-growth cycle — saddled with trade friction, high prices, strained public services and a hyper-sensitive electorate that tolerates virtually no political failure.Chart: Danielle Alberti/AxiosZoom in: Starmer's tenure was consumed by migration and cost-of-living crises, providing ideal conditions for Nigel Farage's right-wing Reform UK to peel away Labour's traditional working-class support.Enter Andy Burnham: The former Greater Manchester mayor and charismatic King of the North is widely seen as the lone Labour heavyweight with the authentic populist appeal needed to blunt Farage's momentum.In a special election engineered to return him to Parliament, Burnham beat Reform decisively, likely clearing the way for him to take over the Labour Party and become Britain's next prime minister.Zoom out: If and when he enters Downing Street, Burnham's greatest challenge will be incumbency — a proven liability across the democratic world in the years since COVID.In France, Emmanuel Macron's approval rating has at times fallen as low as 11, while the far-right National Rally is polling as the favorite to win next year's presidential election.In Germany, the far-right AfD has made unprecedented gains and continues to widen its lead over Chancellor Friedrich Merz's conservatives.In Hungary, voters ended Viktor Orbán's 16-year rule this April, toppling the most entrenched nationalist government in the EU.Between the lines: Even President Trump, who faces a treacherous midterm test in November, is proving vulnerable to the same toxic anti-incumbent forces.His 2016 victory was intertwined with Brexit's geopolitical shock — a warning that voters across the West were willing to torch the establishment to express disgust with migration, globalization and elites' failures.But now Trump is the establishment. High prices and the Iran war have dragged his approval into the high 30s. The world's most successful anti-system politician is suddenly struggling to run against a system he controls.The bottom line: A decade after voting to take back control, Britain is trapped in a state of political paralysis. Ten years of systemic chaos have proven that channeling anti-establishment fury is remarkably easy — but governing it is practically impossible.