Burnham’s entire political brand rests on looking like he just rolled out of a focus group on the Manchester tram. The man has built a career on the strategic deployment of the open-necked shirt, the rolled-up sleeve, the carefully curated air of someone who has better things to do than iron. It is, in other words, completely incompatible with the Prime Minister’s Office.

No 10 has dress codes. They are unwritten, which makes them worse. They are enforced by tradition, which makes them immovable. The building expects morning coats at state occasions, dark suits for Parliament, and an absolute prohibition on anything that suggests the wearer has a personality outside the Civil Service.

Burnham’s plan to institute Casual Friday at Number 10 is not a policy proposal. It is a declaration of war against every institutional norm the building has accumulated since 1735. The civil servants are already briefing against it. Buckingham Palace has apparently sent a strongly worded memo about what the King expects to see when the PM shows up for weekly audience. The Telegraph has already written six columns about standards.

Will Burnham cave immediately and return to the uniform of power, or will he spend five years as Prime Minister wearing the same two Reiss blazers while his advisors quietly weep? Neither outcome is good. One destroys his brand. The other destroys the dress code. Either way, someone loses their mind over a button-up shirt.

The real crisis begins when he tries to explain to foreign leaders why the British Prime Minister looks like he’s about to chair a community meeting in Stockport.