Huawei was the pretext, but you couldn’t help but think that Iran was the primary motive for Mike Pompeo’s decidedly undiplomatic visit to London this week. The US Secretary of State’s public dressing down was for Britain one of the most humiliating episodes – and there have been plenty of them of late – I’ve seen in a long time, and can only really be excused in the context of the paralysing chaos into which British government has descended these past two years.