In one legislative chamber, a British king appealed to centuries of shared history in a bid to preserve his country¡¯s most important alliance. In another, an ocean away, a British prime minister watched his agenda get sidelined again by his past efforts to protect the U.S.-U.K. "special relationship.¡±

The twin scenes, playing out in Washington¡¯s House of Representatives and the House of Commons in London, illustrated how much managing ties with U.S. President Donald Trump¡¯s United States has come to consume the British state. Despite Prime Minster Keir Starmer¡¯s efforts to adapt his left-leaning Labour government to the billionaire Republican¡¯s personality-driven foreign policy, he has watched ties sink to their lowest level in decades.

This week, Starmer deployed the best messenger he could muster to reach a president who is unusually comfortable associating himself with royalty: King Charles III. The 77-year-old monarch¡¯s state visit to Washington ¡ª ostensibly to mark the 250th anniversary of American independence from Britain ¡ª gave Trump the opportunity to hold a military review and a fighter-jet flyover at the White House.