Gordon Brown's first Washington visit as Britain's prime minister has prompted tea-leaf reading about the strengths and weaknesses of the US-UK relationship. Momentarily diverting - and probably unavoidable - as the frenzy of speculation is, the real tests lie ahead. Actions ultimately trump semiotics in national security affairs.

Moreover, as contentious and important as Iraq is, it is a mistake to think that disagreements on that issue represent a fundamental change in the US-UK relationship. Tony Blair and President George W. Bush disagreed on global warming, as will Mr Brown and Mr Bush, but in neither case does the disagreement reflect a tectonic shift.