Labour cannot be saved as long as Jeremy Corbyn is in charge

The final scene of Monty Python's Life of Brian sees the comrades of the eponymous hero rushing to see him on the cross. But rather than rescue him they merely read out a motion of support, before singing For He's a Jolly Good Fellow and leaving him to his fate.

The scene came to mind as Labour MPs expressed "solidarity" with Luciana Berger, their former colleague forced to leave the party after suffering anti-Semitic abuse.

There are so many good Labour MPs who are decent, passionate and committed to their constituents that it ought to be possible to believe the party can be salvaged. But it cannot as long as Jeremy Corbyn and those around him are in charge. Under his leadership anti-Semitism and misogyny is indulged; brutal anti-western dictators are admired, while internal critics are bullied and abused.

You had only to look at the torment in the eyes of Labour MPs such as Stella Creasy and Jess Phillips as they listened to Ms Berger in a Commons debate last week to understand the hopelessness. Their faces betrayed the inner conflict of those who must decide whether they can bring themselves to tell voters that Mr Corbyn should be prime minister.

A close colleague, someone who originally agreed to serve under Mr Corbyn, has just been hounded out of the party by anti-Semitic abuse. But all her mortified friends can do is sit sorrowfully, pledging solidarity and vowing to fight on.

Or look at Angela Rayner, a manifestly decent frontbencher talking about how Mr Corbyn "reached out to Luciana" (it turns out he didn't) as if all she needed was a pat on the shoulder. Previous leaders would have suspended Ms Berger's local party. Previous frontbenchers would have demanded it. Mr Corbyn and his allies have sided with the persecutors rather than the persecuted.

Luciana Berger was forced to leave the party after suffering anti-Semitic abuse. Jason Alden

The news that deputy leader Tom Watson is forming a group of Labour moderates able to fight their corner may seem welcome. More likely membership of the group will simply aid those hardliners drawing up their hit lists.

For Corbynite activists are targeting any soft-left critic of the leader. Stalwart Labour MPs such as Yvette Cooper, Hilary Benn and Rachel Reeves in Leeds are in their sights; so too Ms Creasy, Ms Phillips, Wes Streeting, and Ms Berger's Jewish Liverpool neighbour Louise Ellman, whom Mr Corbyn has allegedly described as "the member for Tel Aviv".

The irony is that left radicalism is having its moment and could win in Britain. But too great a rupture and the chance will be lost. Most mainstream Labour MPs can support much of the Corbyn economic agenda. And while many of them draw back from the feverish apologia for murderous dictatorships, they certainly back a just settlement for the Palestinians.

The party could easily get behind a left-winger who wanted to unite it. But Mr Corbyn is not that figure and until victory is obviously jeopardised his allies will not replace him. He may yet cost his party victory, but secretly hoping for that is not much of a strategy.

Mr Watson's new group and the Brexit referendum move may staunch the exodus of moderates. But in politics, instincts often matter more than actions because they are the best guide to how you will behave in power.

Mr Corbyn's instincts will not shift and MPs who do not believe he is fit to be prime minister but who stay with the party are like those US Republicans who reassured themselves that Donald Trump would change in office.

As Mr Corbyn's Brexit retreat shows, leaving is what forces change. His headline-grabbing switch on a second vote will ease the pressure but it does not change the fundamentals.

Mainstream MPs should see they can no longer fight Mr Corbyn from within. Labour is his party now. They will have to fight for it from outside. Or they could just keep offering those valuable expressions of solidarity. robert.shrimsley@ft.com