“Can you imagine him as Prime Minister?”

“Yes, he is the Conservative dream.”

This exchange between hard-bitten colleagues in the press room confirmed, if confirmation were needed after the standing ovation in the hall, that Rishi Sunak’s speech had been a success.

Seldom can the doctrine of fiscal responsibility have been preached with such Californian optimism.

“The years I spent in California left a lasting mark on me,” Sunak said. He had worked there with “some of the most innovative and exciting people in finance and technology”.

One of the engaging things about Sunak is that he sounds excited to be addressing the Conservative Party Conference. There is no trace in his manner of a duty reluctantly undertaken.

Just in case he might be suspected of becoming over-confident, he worked in a self-deprecating joke near the start, telling his audience what a joy it had been to meet so many members of the party face to face, and to hear so many of them say, “Wow! You’re even shorter in real life!”

He also worked in a declaration of loyalty to

…. the person who made all this possible…

… the person who delivered a thumping Conservative majority…

…my friend, our leader, the country’s Prime Minister…

… Boris…JOHNSON.”

This was the first word in the official version of Sunak’s text to appear in capitals, but by no means the last. JOHNSON was sitting in the front row, to the right of Sunak, exuding benevolence, nodding his approval at frequent intervals.

Sunak said “mindless ideology is dangerous”, a sentiment with which the Prime Minister agrees. But there followed a passage which it was impossible to imagine JOHNSON uttering:

“I believe in fiscal responsibility.

 Just borrowing more money…

…and stacking up bills for future generations to pay…

… is not just economically irresponsible…

… it is…. IMMORAL.”

IMMORAL is not a word for which JOHNSON has much use. He does not care to political choices in moral terms. Sunak does, and in this recalls the greatest Conservative Prime Minister of modern times, Margaret Thatcher.

But let us not suppose that nothing unites these two statesmen. Both are boundless optimists. Candide meets Candide.

Sunak spoke of his “unshakeable optimism”. Everything is for the best in the best of all possible countries.

Tory pessimists will have derived no comfort from this speech.

“I believe we’re going to make the United Kingdom the most exciting place in the planet,” Sunak added.

Only the Labour Party has failed to get this: “It’s not just that they don’t like us…they don’t even like each other.”

An enjoyable line. Labour, he indicated, is the party for people who suffer from fear of change and fear of the future.

Sir Keir Starmer, the Labour leader, finds himself in danger of being swept away by a tidal wave of optimism.