The Huffington Post:
Few people keep Queen Elizabeth II waiting, especially when she has issued a personal invitation, but President Ronald Reagan managed to do so in 1982 without causing any lasting damage.
It happened in 1982, when the Reagan White House failed to reply in a timely way to a personal invitation from the queen for the president and his wife Nancy to stay with her at Windsor Castle during a planned visit to England.
Formerly Confidential papers made public Friday reveal there were raised eyebrows, and bruised feelings, when Reagan did not answer the sort of invite that usually commands a prompt reply the world over. The queen's invitation was left to languish for weeks – something the British believe is simply Not Done.
"It is really for the president to respond to her invitation, which he has not done personally, something that I have pointed out several times here," writes Nicholas Henderson, Britain's ambassador to Washington, in a memo to the British Foreign Office. "As you know those surrounding the president are not deliberately rude: It is simply that they are not well-organized and do not have experience of this sort of thing."