At 10:15 one morning last week, the wooden gates of Copenhagen's grey Amalienborg Palace swung open. Red-jacketed Royal Life Guards sprang smartly to attention as a Rolls-Royce bearing King Frederik IX and his pretty daughter turned slowly into the street. The day belonged to Princess Margrethe.
At Christiansborg Palace, home of the Folketing (Parliament), the 18-year-old princess was formally introduced to the Council of State, and with a gold pen signed an oath to uphold the Danish constitution. Later, as she drove home in a royal coach, crowds jammed the sidewalks to cheer her. They called again and again for...