1. They still represent European colonial power in much of the world.
2. They have shown tremendous weakness in the past concerning their kidnapped sailors (remember the female sailor being put in a Burks?).
3. Obama has made it clear that there is no longer a special relationship between the UK and the USA.
4. They have no capability on their own to stand up to Iran militarily. Their capability is a shadow of what it was during the Falklands (and it was weak then).
I’m not sure where the danger is....other than showing talks with Iran are worthless.