In theory, victory for Boris Johnson in Monday’s vote means he cannot face another no-confidence motion for a year, securing his position in Downing Street. In reality, his position is different.
Weakened prime ministers are vulnerable to plotting, and their authority can be further undermined by rebellions among lawmakers in Parliament that make it impossible to get key legislation through.
Resignations by ministers — particularly senior ones — can deal serious damage to leaders, particularly if they are orchestrated. Mr. Johnson’s cabinet is heavily made up of his supporters, making this less likely, but it is not impossible. For example, there were rumors this year that Rishi Sunak, the chancellor of the Exchequer, might quit; and if Mr. Johnson were to try to demote him in a reshuffle, such speculation could return.
The rule that there can be no repeat of a no-confidence motion for a year could also be changed by the senior hierarchy of the Conservative Party in Parliament.
Even a threat to do so has been enough to persuade a prime minister that her or his time in Downing Street is coming to an end. That was the case for the previous prime minister, Theresa May, who survived a no-confidence vote in December 2018 but announced her resignation within six months of her victory after relentless pressure.
So if enough Conservative lawmakers conclude that they want to ditch Mr. Johnson, there are still ways to force him out.