On the second day of his four-day visit to the United States, King Charles III addressed a joint session of Congress. This trip was timed to coincide with the 250th anniversary of the former British colony's independence. King Charles III and Queen Camilla returned to the White House on Tuesday for a State Dinner hosted by President Donald Trump and First lady Melania Trump. Among the guests expected to be in attendance are Apple CEO Tim Cook and Salesforce CEO Marc Benioff.