Britain's prime minister is stepping down after a revolt inside his own party, deepening years of political chaos in a major economy — bad news for stability.

• Keir Starmer quit as Labour leader after his own lawmakers turned against him, but stays on as PM until a successor is picked.
• He was badly damaged by getting too close to Trump on letting US strike Iran from British bases, and by ties between his ambassador pick and Epstein.
• This would be Britain's sixth prime minister in seven years, a run of turmoil that started with Brexit a decade ago.
• Left-winger Andy Burnham is the favorite to take over, promising to fix the economy, cost of living, and housing.
• Whoever wins inherits a weak economy, high taxes, rising debt, and pressure to spend more on the military — with no clear way to pay for it.

Outlook: Labour will pick a new leader by September, likely Burnham, but the deeper economic and political problems will stay.