Ever country has a protocol officer and part of their job is to specify how one is supposed to treat the Head of State. In America, for example, you must always refer to the President as Mr. President and unelected cabinet ministers are addressed as Mr./Madam Secretary [Office of the Chief of Protocol].
Visiting Heads of State are expected to conform to American protocol and when the President visits another country he is expected to conform to their rules of protocol. That's how international diplomacy works. It's a system that has evolved over several centuries to try and makes things easier when two different countries communicate. The idea is for countries to respect each other.
Postdiluvian at The Unexamined Life doesn't think that Americans need to respect the protocols and traditions of a foreign country [Is it OK to hug the Queen?]. Now, as it turns out, Michelle's hug was a breach of protocol but not that big a deal, even in England. It would be comparable to someone forgetting to say "Mr. President" when addressing Barack Obama.
That doesn't justify this kind of response ....
Now here’s the bottom line: you can have your “Queen” as a powerless (and utterly pointless) figurehead if you like. She can even keep her massive wealth that somehow came into her family’s possession over the centuries. But if you ever start this bullshit about “Royal Protocol” again, or whether or not it’s okay for people to touch her, you will be removing yourself from the realm of the Serious and joining the realm of Laughingstock, much like the concept of Monarchy did ages ago.Americans often wonder why they have so much trouble making friends in "foreign" countries. I can't imagine why.