From the latest YouGov poll:

The answers to this question have bobbled up and down over time, both in response to events and normal sampling fluctuations. There is a persistent pattern, however. Even when the Conservatives are riding high in the polls and Theresa May’s personal ratings are strong, the public’s view of how the government is handling Brexit is, at best, mixed for the Conservatives.

Which makes this a major vulnerability for the government. Being seen as competent is an important part of not only Theresa May’s appeal but also for political parties in general. When that goes, the fortunes of a party can disappear down into repeated defeat for years to come – witness past Conservative and Labour experiences.

What’s more, the question of competence over Brexit opens up a route for people who voted Leave to back anti-Brexit opposition parties .

People are much more likely to change their views in response to new information than in response to being told they were wrong. Attacking the government for handling Brexit badly is a better way to persuade Leave voters to vote Liberal Democrat, and even support Remain, than telling them they got it wrong last year. (Or, even worse, that they were stupid and should just fess up to their own stupidity.)

A Prime Minister who disdains more media management yet is well known for a trademark visual device. A Prime Minister whose low-key approach is initially praised for quiet competence. A Prime Minister whose initial popularity turns around the fortunes of their party and sets it off on a series of record-breaking electoral successes. A Prime Minister whose party’s seeming electoral invincibility led to a flurry of opposition talk about the need for deals, pacts and realignment.

John Major, his soap box and the 1992 general election. Or Theresa May, her shoes and Copeland?

Major’s tenure ended in scandal, landslide defeat and a record-breaking run of electoral defeats. Yet early on he and his party appeared set for years of political dominance. That Brexit competence question is the key figure to track to judge how likely a repeat of all that is.

I spoke more about this in the recent Polling Matters podcast, which you can listen to here.

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