Even an awkward bit of friendly fire in the form of leaked comments which emerged from the UK’s own ambassador to the US couldn’t take the sheen off the King's charm offensive, says Helen MacNamara Sign up for our free Voices newsletter for expert opinion and columns Sign up for our free weekly Voices newsletter for expert opinion and columns Sign up to our free weekly Voices newsletter Email * SIGN UP I would like to be emailed about offers, events and updates from The Independent. Read our