For the Labour Party I love, the party I have devoted more than 50 years of my life to serving, the re-election of Jeremy Corbyn as leader is a catastrophe.

I’m in despair at this calamitous situation. I honestly cannot see how we’re going to get out of it.

Most readers, of course, will not be lifelong party members like me. Perhaps you think that this is merely a Westminster matter.

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David Blunkett: For the Labour Party I love, the party I have devoted more than 50 years of my life to serving, the re-election of Jeremy Corbyn as leader is a catastrophe

Jeremy Corbyn’s position as leader of Her Majesty’s Opposition has been reinforced by a vote, and that’s just politics. Does it affect real life?

The answer is a resounding yes.

This is about the immediate future of British democracy. There has to be a credible opposition party, one that the wider public can trust.

If not, there will be a permanent Conservative majority in the Commons, with nobody to keep the government honest and accountable.

And even for the most dyed-in-the-wool Tories that is very bad news. For the country, it’s an utter disaster. Everyone should be as concerned as I am.

The Labour Party under Corbyn is not electable. I am at a loss to understand what the 313,000 members who voted for him believe they can really achieve in the next three years, and what the eventual outcome will be, other than annihilation at a general election in 2020.

They have shown that they are completely disconnected from the broad electorate and, when that happens to a party, it ceases to be relevant.

That’s my worst political nightmare – a Labour Party that doesn’t connect to the lives of ordinary working people.

Jeremy Corbyn’s position as leader of Her Majesty’s Opposition has been reinforced by a vote, and that’s just politics. Does it affect real life?

Much of the support for Corbyn exists on social media, in online forums such as Facebook and Twitter.

I can appreciate that for the activists constantly parroting each others’ soundbites, it must be deeply satisfying to be surrounded by the echoes of their own voices.

But it’s a terrible mistake to imagine that noise is the voice of the whole country.

With the backing of Britain, Labour leaders in the past have achieved massive social changes. We did not establish the National Health Service by being a protest movement.

David Blunkett, former Labour Home Secretary from 2001-2004

We did it by uniting millions of people. And that’s what Jeremy Corbyn can never do.

He’s a past master at the art of opposition. He’s been opposing the government, whether it’s Tory, Labour or Coalition, since he first entered the Commons in 1983.

And that’s all he can do. He could never lead a government, because he has no experience of it and no aptitude for it.

My own experience tells me so. I joined Labour when I was 16 years old in 1963, the year The Beatles had their first No 1.

I became the youngest member of Sheffield City Council in 1970, and I was elected leader of that council ten years later.

My own politics were left of centre, but I was able to work with men and women with widely differing convictions because we all wanted the same thing: a Labour government.

That’s why, as part of the National Executive, I was instrumental in fighting and expelling the Trotskyite Militant Tendency during the 1980s. Some of those people are the same ones who are steering the Momentum organisation that now backs Corbyn.

Labour is my lifeblood. All of us who love the party have to fight to take it back. But that doesn’t mean a knee-jerk reaction, setting up an alternative movement to seize the middle ground. If we attempt to do that, without thinking it through very carefully, we’ll be doomed to failure.

My worst political nightmare – a Labour Party that doesn’t connect to the lives of ordinary working people

The Corbyn wing controls all the money and the party machinery, for a start. MPs who try to break away will be powerless.

I was against the peremptory move to dislodge Corbyn this summer, because we weren’t prepared for the battle. We hadn’t made enough of an effort to recruit ordinary people to the party, to combat the extremists. And we didn’t have any clear idea of our goals, other than ‘Corbyn must go’.

It would be madness to carry on like that. We have to stop, take deep breaths and start talking.

For those who demand acquiescence and see even the writing of this article as betrayal, I have one question: Do you really believe that repeating someone else’s message, and swearing that Jeremy can lead Labour to victory, can change reality?

The great political novelist George Orwell wrote in the late 1930s that the problem with Marxists is that they don’t have any clue what’s going on in normal people’s heads. That’s as true today as it was before the Second World War.

Much of the support for Corbyn exists on social media, in online forums such as Facebook and Twitter

The people running Momentum are modern-day Marxists. And they are incapable of seeing that Britain will never vote for Jeremy Corbyn as prime minister, when he has no concept of national security.

He doesn’t want to fight terrorism – he can’t even bring himself to denounce Palestinian terrorists or the IRA.

He has already said he would never push the nuclear button, and I strongly suspect he could never sanction any kind of war at all. A Britain led by this man would be vulnerable and helpless, and the electorate knows it.

All the Twitter and Facebook slogans in the world won’t change that.

Labour is a great party, founded by great men. I ask myself what our past leaders, visionaries such as Keir Hardie and Clement Attlee, would make of this current mess. I strain to hear their voices down the ages, and I think they would be as speechless with dismay as I am.