Lessons in leadership: Jeremy Corbyn can afford to play down the scale of his setback on Trident – but he must sharpen up his act

Jeremy Corbyn took a risk when he supported putting Trident up for a vote at his first Labour conference at which he was presiding as leader. Now he has been saved from humiliation in open conference after the committee of delegates – anticipating defeat at union hands – yanked the expected vote off the agenda.

Mr Corbyn’s legion of detractors will present this feeble, face-saving device as proof of his weak leadership and talk up Labour splits over Britain’s nuclear deterrent. In reality, the setback is on a more modest scale precisely because Mr Corbyn has made a point of championing the virtue of honest disagreement. Indeed, he might describe his apparent defeat over Trident as proof of the sincerity of his intention to conduct a new kind of politics not based on top-down diktats.

Before the conference opened, while restating his strongly held view that Britain should give up “weapons of mass destruction”, Mr Corbyn pointedly declined to make opposition to the renewal of Trident a form of loyalty test, adding that he understood the very different views held by some of his colleagues, including his deputy, Tom Watson.

In reality, the odds were always stacked against Mr Corbyn being able to turn the Labour Party against Trident overnight, after decades in which it has supported Britain’s right to retain nuclear weapons. Apart from Mr Watson, key figures in Team Corbyn, including the shadow Justice Secretary, Lord Falconer, had made it clear that they were not interested in hearing Mr Corbyn’s arguments and might even quit their posts if the party adopted them as official policy.

Lord Falconer was only the most voluble of a large group of dissenters, moreover. Most members of the Shadow Cabinet appeared to back the renewal of Trident. Most Labour MPs certainly do and, as Mr Watson had suggested that Labour MPs might be allowed a free vote on Trident when it goes before Parliament next year, there was never a question of the Government risking defeat on the issue.

What sank it for Mr Corbyn, however, was not opposition from the Shadow Cabinet but from the unions. Both the GMB and Unite, the party’s most important financial backer, said they saw tens of thousands of jobs in defence as the priority, which left only Unison among the big players on Mr Corbyn’s side.

Mr Corbyn’s supporters are tireless in their insistence that winning every argument or, indeed, election is less important to them than “changing the conversation”. In that sense, they can draw some comfort from this débâcle. Bipartisan support for nuclear weapons can no longer be taken for granted in the way that it has been until recently.

However, Mr Corbyn needs to learn lessons from what happened. Labour’s new leader cannot endlessly punt policies that his own party then either ignores or shoots down without suffering serious long-term erosion of his authority. Labour activists may be enjoying Mr Corbyn’s conversational tactics for now. Sooner or later, they will expect him to lead as well as float ideas.