For the best part of 48 hours, first the defence secretary and then the foreign secretary were struggling to cogently articulate in public what the government made of the US and Israel's attacks on Iran and why.
But in the Commons the prime minister directly and explicitly set out his view, when he told MPs the government "does not believe in regime change from the skies".
He was also explicit in acknowledging his disagreement with President Donald Trump – perhaps his biggest and most consequential such disagreement yet.
Sir Keir Starmer took questions from MPs for around two-and-a-half hours, spelling out that he thought the American and Israeli actions were not right and implying there were not lawful either - but that it was both right and lawful to authorise the US to use UK airbases to bomb Iranian missile launch sites, in order to protect British allies in the Gulf from attack.
The memory of the Iraq war was referred to repeatedly across the chamber, including by the Prime Minister.
