Was Michelle Obama’s embrace of the Queen a breach of protocol? I really don’t care, but this is what the media is talking about today. Times of London:

When Michelle Obama put her arm round the Queen at Buckingham Palace, some of the more excitable elements of the media — particularly the Americans — suggested she may have been guilty of a breach of protocol.
They missed the real story, however. What was far more interesting was that the Queen put her arm round the First Lady.
It is less than 20 years ago that the Australian Prime Minister was branded “the Lizard of Oz” for committing the supposedly heinous crime of putting his hand on the Queen’s back during an official tour of Australia.
Now the Queen is not just putting up with physical gestures of affection from a woman she has only just met, but is reciprocating with one of her own.
The footage does not make it clear who made the first move. But given the Queen’s track record — she is not a woman known for doing warm, at least not in public — the fact that Mrs Obama is American, and that the President spent most of the first part of the day putting his arm round Gordon Brown, it can safely be assumed that it was the First Lady who took the initiative.