Jeremy Corbyn took Labour's top job promising a "kinder" politics but the historic vote authorising military action in Syria has plunged Labour into deeper turmoil.
The leader’s fragile authority among his parliamentary party was strained further after he ricocheted into a messy compromise to stave off the collapse of his shadow cabinet.
After setting out the case against air strikes in the Commons, the pacifist found himself out-performed by his shadow foreign secretary, Hilary Benn, who gave a bravura speech supporting military intervention.
Benn’s impassioned plea to Labour colleagues not to “walk by on the other side of the road” was met by loud cheers from across the House and has been widely lauded outside.
But the commanding performance has served to highlight only further how divided the party is.
Calls for Benn to become leader quickly began to trend on Twitter and Corbyn ally Ken Livingstone pointedly claimed the speech "could have been the opening of a leadership campaign".
But it also sparked a wave of vitriol among opponents of military action, including roundly condemned comments by the Scottish National Party MP George Kerevan that Benn's Labour stalwart father Tony would be "turning in his grave".
Protesters demonstrated outside the constituency offices of several MPs and some were the targets of social media campaigns that flooded their accounts with images of dead babies.
Bullying
As the debate went on Corbyn was forced to issue a plea to party members to behave respectfully as the allegations of bullying and intimidation against those preparing to support the Government grew.
But the public declaration is likely to do little to distance the leader from claims that those on Labour’s right wing face being purged from the party.
Labour sources insisted that Corbyn had shown leadership and that the vote result demonstrated that he had a “clear majority in all parts of the Labour Party” for his position.
Corbyn's inability to persuade 11 members of his shadow cabinet, including Benn, deputy leader Tom Watson and defence secretary Marie Eagle, undermines him yet further with the parliamentary party.
But his popularity with the wider party, however, affords the leader significant protection and makes it difficult to remove him.
And his allies have made clear there will be recriminations for those who walked through the voting lobbies with the Government with indications they face de-selections.
Shadow energy minister Clive Lewis warned colleagues voting in favour "on their heads be it" while Livingstone said he would be prepared to support a challenge to a war-supporting MP.
As the deep hatred between the factions shows little sign of abating, Corbyn’s promise to “cut out the personal abuse” and bring about a “gentler” politics appears to be further away than ever.
PA