When Tom Watson, the deputy head of Britain’s opposition Labour party, was asked this week if his boss, Jeremy Corbyn, was fit to become prime minister he struggled to answer.
“He could easily be . . . but we could do without the anti-Semitism,” he said in an interview with the BBC.
Mr Watson’s comments encapsulate a longstanding power struggle between the two men that has been intensified by the resignation of eight Labour MPs last month over Mr Corbyn’s leadership on issues ranging from anti-Semitism to Brexit.
The stand-off is part of a wider split between the party’s moderates and the hard left that has raged since the leftwing Mr Corbyn was made leader in 2015.
In recent days Mr Watson has dropped any pretence of lauding the Labour leader, stepping up efforts to stamp out pockets of anti-Semitism and forcing the suspension of Corbyn ally Chris Williamson over the issue on Wednesday.
He has also formed a “national policy forum” for centrist Labour MPs that has been dubbed “a party within a party” by his supporters.
“He is throwing his weight around, that’s for sure,” said a Corbyn ally. One friend of Mr Watson said that he has “suddenly woken up politically”.
Mr Corbyn may dislike his deputy, but he needs him if he is to fend off a bigger schism in the party in the coming months. “The only thing stopping me from leaving the party right now is Tom Watson,” said one life-long member.
The limits to the Labour leader’s power were demonstrated this week when he was manoeuvred into backing a second Brexit referendum by a handful of shadow cabinet colleagues, including Mr Watson.
This was a major climbdown by Mr Corbyn — a life-long Eurosceptic who said last year that “the ship has sailed” on stopping Brexit. Senior Corbyn aides and high-ranking MPs — including party chairman Ian Lavery — were also adamant that the party should resist a rerun of 2016 that could alienate working-class voters in the north of England and the Midlands.
But Mr Corbyn has been struggling to stem a rising tide of anger from hundreds of thousands of pro-European party members who want to block Brexit.
A key instigator of the policy shift was Sir Keir Starmer, shadow Brexit secretary, who has pushed steadily for the change since early last year. “Keir’s persistence is the only reason it is happening,” said one shadow cabinet source.
The intervention of two of Mr Corbyn’s oldest political friends — shadow chancellor John McDonnell and shadow home secretary Diane Abbott — was also important.
“It did not seem right that we should have the leader at odds with the members, that would have been a problem,” said Ms Abbott. “The majority of members wanted a People’s Vote and also there was a party democracy issue.”
As recently as last autumn, when the Labour party conference agreed an oblique motion that made a second referendum on leaving the EU an “option” — albeit not the preferred one — Mr McDonnell had initially insisted the ballot would not include a Remain option.
But the shadow chancellor, while as fiercely leftwing as Mr Corbyn, is determined to hold Labour together in the pursuit of power. He saw backing another referendum as a way to prevent further rifts in the party, as did shadow foreign secretary Emily Thornberry.
Influential senior aides to Mr Corbyn — including Seumas Milne, head of strategy, Karie Murphy, chief of staff, Andrew Murray, an adviser and former communist, and Len McCluskey, head of the powerful Unite union — remained opposed.
That changed with the dramatic walk out of Luciana Berger, Chuka Umunna and six other MPs and the formation of the pro-EU Independent Group. “TIG expedited things,” admitted one close Corbyn ally.
This in turn empowered Mr Corbyn’s deputy. “Our departure has given Watson leverage in the party,” said one of the departing MPs. “He can warn of a further exodus unless people listen to him.”
Speculation in Westminster that 70 MPs were considering quitting the party last month may be over-blown, but is hard to disprove. Some believe Mr Corbyn’s core supporters have a list of about 50 MPs they would love to remove — although this is denied by the leader’s office.
Meanwhile, Mr Watson’s manoeuvring is causing consternation among pro-Corbyn MPs. “When John Prescott was deputy prime minister he disagreed with Tony Blair on almost everything but he never tried to throw his weight around like this,” said one.
Some believe Mr Watson could be swept away if a figure loyal to the Labour leader mounted a challenge for the deputy leadership. But one Corbyn ally is sceptical: “What would that achieve? We’d have yet more months of headlines about Labour being at war, no one wants that.”
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