The British are known to take matters of heraldry seriously, and Mr. Trump's American coat of arms belongs to another family. It was granted by British authorities in 1939 to Joseph Edward Davies, the third husband of Marjorie Merriweather Post, the socialite who built the Mar-a-Lago resort that is now Mr. Trump's cherished getaway.

In the United States, the Trump Organization took Mr. Davies's coat of arms for its own, making one small adjustment -- replacing the word "Integritas," Latin for integrity, with "Trump."