The drama affecting shipping in the Strait of Hormuz is not quite yet a full-blown crisis – characterised as it is by plausible deniability for Iran on attacks on tankers in the Gulf of Oman and dubious claims on the legality of other vessels seized by the Islamic Revolutionary Guards Corp (IRGC). It does though represent a serious foreign policy dilemma for the newly-installed government of UK Prime Minister Boris Johnson, at a time when the British authorities already have an over-full agenda trying to avoid a chaotic exit from the European Union (EU) on 31 October.