Brexit will endure after Sunak’s deal, but Brexitism is dying and Johnsonism may be dead

‘Ursula von der Leyen attributed the breakthrough to ‘honesty’ and ‘goodwill’ made possible by ‘a constructive attitude from the very beginning’.’ Photograph: Dan Kitwood/AFP/Getty Images

Brexit is done and also it will never be done. Rishi Sunak’s deal to fix the Northern Ireland protocol ends a process that is only beginning. If that sounds paradoxical it is because British politics uses the B-word to describe many things, or rather it confuses different things by pretending they are one.

Brexit was an insurrection against the status quo and a promise to upend the established ways of Westminster government. But Brexit is also a technical project and a diplomatic minefield that can’t be navigated without those old skills of establishment statecraft.