Jeremy Corbyn knows that he is a leader who does not have the support of many of his MPs. This was why, in his set-piece speech to the Labour party conference in Brighton, he made pointed reference to his “mandate” and the many tens of thousands of new party members whose wave of adulation carried him to victory. If he is to succeed, he will have to bypass his MPs and work through the members and activists as he seeks to create a “more caring” and “kinder” society. Mr Corbyn’s phrase for his approach, used again in his speech, is “bottom-up” politics.

The politics of Mr Corbyn and his most loyal ally, John McDonnell, now an improbable shadow chancellor, were forged during the Bennite wars of the early 1980s. For them the annual conference, not the parliamentary party, is the forum in which policy should be decided. First, they have to get their supporters represented on the conference floor and in the key decision-making bodies of the party, such as the National Executive Committee (NEC). This process has begun: Rebecca Long-Bailey, a supporter of Mr Corbyn, has replaced Hilary Benn, the shadow foreign secretary and a noted moderate, on the NEC. Community, which backed Yvette Cooper in the leadership race, has been replaced by the more left-wing bakers’ union.

Mr Corbyn’s speech was long, at just under an hour, and respectfully received in the hall. It was, on the whole, repetitious, without structure, devoid of arresting phrases apart from when he quoted the novelists Maya Angelou and Ben Okri, and delivered haltingly. It used sections sent in by a writer who had offered the same passages to every Labour leader since Neil Kinnock.

Mr Corbyn attacked the loathed media, notably the “commentariat”, as well as hedge funds, Saudi Arabia and the Tories. He spoke repeatedly in praise of solidarity and diversity. There were restatements of his core beliefs and of his hatred for inequality but very little on education and home ownership. However, his aspiration to build 100,000 new council houses a year is necessary and admirable.

More troublingly for a party that was routed in Scotland and, excluding London, has only 11 out of 197 seats south of the metaphorical line that runs from the River Severn to the Wash, no attempt was made to address a sceptical wider electorate. He did not mention Labour’s general election defeat in May or even attempt to discuss the reasons for it. Yet Mr Corbyn’s great strength is his conviction. If he goes down in flames, he will do so on his own terms, in his own way.

The Labour leader was not helped by the absence of a large faction of Corbynistas in the conference hall. Most of the delegates representing their constituency parties were long-time members, rather than the new recruits who joined after the general election or paid £3 to vote as “supporters”.

All of this, as well as the desire of senior MPs (notably the new deputy leader, Tom Watson) to respect Mr Corbyn’s mandate, has given events in Brighton the feel of the early exchanges in a phoney war. The serious battles – on Trident renewal (Mr Corbyn has reaffirmed his unilateralism); opposition to welfare cuts and a benefits cap; the mandatory reselection of MPs – have been put on hold.

Indeed, the luminous late-summer sunshine in Brighton contributed to the sense of unreality. First, the defeat in the general election and then the arrival of an unexpected leader: MPs are grappling to understand the new world in which they find themselves.

Away from the main conference, at fringe meetings and in the bars and cafés of the seaside town, there was intrigue and conspiracy. The self-described “moderates” who have refused to serve in the shadow cabinet are already plotting. They are also embracing a new culture of open debate and of what one called “creative destruction”.

Mr Corbyn is convinced that he is the harbinger of a new politics and he has certainly acted as a catalyst for a kind of enthusiasm unseen in the Labour Party since perhaps the early 1960s. No one can doubt that Labour is on the brink of convulsive change.