Keir Starmer faced his biggest challenge yet on Wednesday when his health minister was reported to be readying his resignation to try to trigger a contest to replace a British prime minister who had sought some respite to set out his government’s agenda. As Starmer and his ministers stood in silence to hear King Charles read out their government’s agenda, the ceremony was overshadowed by what could be the most dangerous threat to the prime minister since lawmakers began urging him to resign over...