https://www.npr.org/2022/09/12/ [login to see] /from-truman-to-biden-the-queens-meetings-with-presidents-were-formal-fun-or-awkw
The death of Queen Elizabeth II closes a chapter in British history that lasted seven decades. But beyond the years, there's another way to mark her reign: in her lifetime, the queen met with a procession of 13 different U.S. presidents. The names and faces of the American head of state kept changing — while the queen and her crown remained a constant.
Her title was still Princess Elizabeth when she arrived in America for the first time in October 1951. Dignitaries on hand to meet the future queen on the crowded tarmac at Washington National Airport included President Harry Truman.
"It certainly is a very great pleasure for me as president of the United States to welcome you to the capital of our country," Truman said, adding, "I think your visit will improve — if that is possible — the cordial relations that exist between our two great countries, and I hope that while you are here you will have a very enjoyable time."
The 25-year-old Elizabeth — with husband Philip by her side — was there to represent her ailing father, King George VI.