Washington, April 28 -- In a moment steeped in both ancient tradition and modern urgency, King Charles III became only the second reigning British monarch to address a Joint Meeting of the US Congress on Tuesday (local time).

Speaking in the House Chamber during the United States' semiquincentennial (250th) anniversary year, the King delivered a stirring tribute to the "indispensable partnership" between the two nations, even as he acknowledged the "weight of history" and the scars of recent global conflicts.

The King opened with a masterful nod to the shared origins of the two republics, jokingly referring to the American Revolution as a "fundamental disagreement" between his five-times great-grandfather, King George III, and the Found...