After several months of brinkmanship, Britain’s Conservative government has decided to launch a direct assault on the Northern Ireland Protocol of Boris Johnson’s Brexit agreement. Instead of haggling with the European Union for concessions over the way it operates the protocol, Johnson’s foreign secretary, Liz Truss, has announced legislation to override it altogether. The EU has responded with threats of legal action and a trade war.

It’s hard to disentangle the long-term strategy that may underpin this move from more immediate political concerns. Johnson has recently survived a no-confidence vote in which two-fifths of Conservative MPs wanted him to resign as party leader. Truss is positioning herself for a future leadership contest if Johnson falls at the next hurdle.

One thing is perfectly clear, however. The latest post-Brexit crisis, with its destabilizing implications for Northern Irish politics, is the price for Boris Johnson’s electoral triumph at the end of 2019. A range of political actors in Britain — including some of those who are now deploring Johnson’s behavior — gladly chose to pay that price because they were so hostile to the alternative: a left-wing government with a reform program that might have begun to repair the country’s social fabric after decades of ruling-class vandalism.