It is foolish to read too much into body language, but what we saw in Dublin on Monday morning was startling. The Taoiseach was calm, clear, sure of his tone, which was neither aggressive nor ingratiating.

Boris Johnson was deeply uncertain, unable to stand still at the podium, hesitating between tones – patronisingly matey or grandly demanding? He exuded, not the confidence we would usually take for granted in a visiting British prime minister, but an unease bordering on complete disorientation.