"Corbyn and his allies care more about controlling Labour than winning the election" claims my IBT colleague James Bloodworth. Well, I counter with: Anti-Corbynites on the left care more about deposing the Labour leader than winning the election.

Jeremy Corbyn has been as divisive a figure within Labour as Tony Blair was back in the 90s, when the left of the party was marginalised and sometimes banished. The remaining pillars of Blairism within the party are the MPs and the Labour supporters who were drawn to it (and him) when the movement was at the most centrist point in its history.

They often argue that it was only by becoming such a middle ground party that Labour's electoral victories of 1997 and beyond became possible. This is to forget that that Tory government was so despised after 18 years of power that a red-rosette-wearing-hamster could have beaten John Major & Co.

Unfortunately for the New Labour rump of the parliamentary party, Corbyn has found massive support within the movement, which has re-energised the faithful and boosted membership to a level not seen since the 1970s.

But the New Labour MPs and the commentariat think that they know better and have constantly attempted to destabilise the leadership.

Corbyn has already been elected twice to his job, the second time after a leadership challenge was launched by New Labour when they really should have been focusing on a larger issue — it was the day after the biggest vote in modern UK history had declared for Brexit.

It is natural that the right-wing media (which is the vast majority, particularly in terms of circulation) should attack Corbyn and his policies. But too often the attack dogs are not growling at his policies – for too much investigation of these might lead people to see that they are well thought through, costed, and to the benefit of 99% of the population. Instead they make him a personal figure of ridicule and suggest that he is unelectable.

Sadly, too much of the left and liberal media have joined this character assassination and prejudged Corbyn as an electoral liability.

Thus the mainstream media is almost universally declaring that Labour will be annihilated in the forthcoming general election. While Theresa May was talking about reintroducing fox hunting and spending another day avoiding real questions about actual policies, the Guardian's headline was: "Jeremy Corbyn says he will not quit as Labour Leader if he loses election".

This downbeat narrative, blaming Corbyn and his policies, seeps through society. Across my social media accounts, I see too many people I think of as comrades in arms declaring that Corbyn has no chance and must go.

What message does this send to the other side? The Conservative Party's strategy has become keep-your-heads-down-and-let-the-opposition-get-us elected. Tory voters, cocooned in their Daily Mail/Sun/Telegraph view of the world, are laughing their socks off.

But what about floaters and undecideds? Are they going to be swung to support a leader and party that receives so much venom from its own "supporters"?

Drawing particular favour amongst the anti-Corbyn centre-left is the idea of a progressive alliance to fight the Tories. That Corbyn has not supported this plan leads to further ridicule and abuse.

Key to this policy, of course, are the Liberal Democrats, who, lest we forget, last formed a political alliance with another party just seven years ago. It was with the Tories. The centre-left was furious with the Lib Dems then, but now we are supposed to embrace them as progressive allies? Beating the Tories is a worthy ambition, but if the Lib Dems win enough seats to hold the balance of power there is no guarantee which side they will join.

It seems very much as though elements of the centre-left would rather lose this election – thus making their predictions of Labour's defeat a self-fulfilling prophecy – in order to get rid of Corbyn. But five more years of this Conservative government could be too late to salvage anything from the wreckage around us.

The NHS is close to collapse and threatened by privatisation by stealth. The gap between rich and poor grows ever deeper and more divisive. So too the distance between Britain and Europe. Five years of this "no deal is better than a bad deal" government could not only lead to a divorce from Europe but a distinctly unamicable future relationship.

Let's leave aside Corbyn's "personality" – although personally, I am in favour of a man who has principles and can demonstrably to be shown to be on the right side of history so often – and look at the policies.

Who on the left (or even centre) is opposed to properly funding the NHS, putting money into education, axeing tuition fees, all funded by making the rich pay their fair share? Refusing to launch nuclear weapons ought to be the policy of anyone who wants humanity to survive.

What is the alternative? Tories promising "strong and stable" government, an alliterative way of saying a continuation of the same old policies that have brought the NHS to crisis, poverty rising, the disabled punished, cutbacks in schools, all while the rich continue to grow richer.

This is a message that can be beaten. The left has never needed unity more. Support Jeremy Corbyn now or take your share of the blame for five more years of Tory rule.