King Charles III and Queen Camilla landed in Washington for an official state visit, and the scene in front of the White House was a blend of protocol, politics and a handful of moments world media are already running through a magnifying glass. Trump and Melania welcomed the British guests on the South Portico - red carpet, strict ceremony, and markings on the floor reading "president" and "king" so that nobody stood in the wrong place.

Camilla seems to have stepped on the wrong spot for protocol - or on the right spot for people. Before Trump reached her, she greeted Melania with a kiss, skipping the order that royal protocol has prescribed for decades. By accident or not, it's the detail people are still talking about. Camilla also wore a historic brooch - a gift from Queen Elizabeth II from her visit to New York in the fifties, rubies, emeralds and diamonds - a quiet signal that this is not just a political visit, but a symbolic continuation of a long British-American bond.

Melania wore an olive-yellow ensemble by designer Adam Lippes, while Camilla swapped her travel pink Dior for a white embroidered Anna Valentine dress at the reception. The official program is dense: tea at the White House, a private reception with 650 guests, the king's address to Congress, a state dinner, a tribute to the September 11 victims in New York, and business meetings. The visit runs through May 2.

The charm of these visits is precisely in the details - who greeted whom first, which symbols are worn, which messages get sent without words. The Brits know how to play that protocol chess better than just about anyone. Does Trump appreciate those subtleties? That's a question Congress will answer when the king speaks.