Theresa May has become more vulnerable. An unbroken series of easy victories over Jeremy Corbyn prompted her to call an early general election in which she confidently expected to triumph over him.

Hubris was followed by nemesis. Instead of collapsing, the Labour leader put on votes and seats.

Today he had the effrontery to defend the Conservative manifesto, which he accused her of ditching on contentious subjects like shareholder votes on bosses’ pay: “She’s gone back on her word.”

One can imagine some past Tory leaders remarking, in a wry way, how good it was to hear the Labour leader standing up for the Conservative manifesto.

But May’s weapon of choice is not wit. She dares instead to be dull. Her answers are on the long side, and include the repetition of various home truths which have already been heard many times before.

Today she told us about Labour always calling in opposition for more money to be spent on everything: “The problem with Labour is they do it in government as well.”

So we are to be frightened by the prospect of a Labour government. But May’s manner was so soporific that the greater danger was we would fall asleep.

The most immediate threat to Conservative leaders generally comes from their own backbenches. Anna Soubry (Broxtowe) was worried the EU Withdrawal Bill could become “an unnecessary and unprecedented government power grab”.

The Prime Minister could have remarked, with a wry smile, that it was good to hear Soubry, an outspoken supporter of EU membership, upholding parliamentary sovereignty. Here surely is an admirable consequence of Brexit: that it forces people to take the Commons seriously.

Which May proceeded to do, by pretending she was “very grateful” for Soubry’s intervention, and adding that she would be “very happy” to meet her “to discuss this further”.

There is no end to the paradoxes which might be derived from May’s weakness. If it forces her to listen to her own backbenchers, it could even end up making her stronger.