The night Westminster strangled Corbyn’s new politics

"What [Pat McFadden has] done on a number of occasions is unfortunately distorted Jeremy's views and turned that into almost a personalised undermining of Jeremy. To be frank, if you want to do that, go to the backbenches and express your views."

And with that, the new politics died. Shadow chancellor John McDonnell's comments on the Today programme this morning hammered the final nail into Jeremy Corbyn's internal democracy project.

A million years ago, in September, Corbyn had a rather different message. "Is it so disastrous that politics has two opinions?" he asked Andrew Marr, as they discussed Trident. "We are going to come to an accommodation of some sort. There may end up being a difference of opinion."

It's now clear what happens when a shadow Cabinet minister publicly expresses their difference of opinion with the Labour leader: They either get sacked or they get told to shut up, as shadow foreign secretary Hilary Benn has been.

"[Benn] has recognised the mandate that Jeremy Corbyn has from our members, an overwhelming mandate, and he will recognise his leadership on these issues," McDonnell said this morning. "It will be the leader of the Labour party that will express the parliamentary Labour party's views from the frontbench. It will not be someone who disagrees with that."

So here we are again: back to the old politics. What Corbyn is doing is singularly unremarkable. David Cameron was up to the same thing only yesterday. He announced that his ministers would be able to vote however they liked in the EU referendum. But watch closely for what happens to them afterwards. As with Harold Wilson in 1975: you can vote how you like, but that doesn't mean there won't be consequences afterwards. His ministers will likely consider their careers before they decide to stroll into the wilderness.

Similarly, Benn's impassioned and highly eloquent speech supporting Syrian military intervention won him a public dressing down today. McFadden's clear attack on his leader, in the form of a question to the prime minister about the moral responsibility of terrorists following the Paris attacks, resulted in his sacking. And Michael Dugher's article for the New Statesman warning against a 'revenge reshuffle' seems ironically to have thrown him into the firing line.

He'll be replaced by Maria Eagle, while Trident opponent Emily Thornberry takes over the shadow defence position, thereby opening up the space for a significant shift in the party's position on the issue. Despite the utterly shambolic and long-winded way in which the reshuffle took place, this is actually a relatively canny move. But it is the move of someone who is increasing their control over the party, not someone trying to create a new culture of open debate to replace the supposed tyranny of the Blair years.

That being said, there's something disingenuous about the press response. Most of the coverage would have you believe that Corbyn's targets were innocent victims of their principles. In fact, the efforts to undercut the Labour leader have been pretty tawdry. McFadden's question on terrorism, for instance, was part of a cheap rhetorical manoeuvre in which those suggesting there is a causal link between Western foreign policy and terror attacks are told they are 'victim blaming' those killed by terrorists.

As it happens, I dislike the foreign policy argument. If Parisians were attacked for their government's foreign policy in the Middle East, then exactly what was it the Yazidi did to be butchered by Isis fascists? But that does not mean that those who make the argument should be smeared as not placing moral blame on terrorists. One can say that foreign policy results in terror without taking away the moral culpability of terrorists, just as one might say that poverty makes it more likely that someone will commit acquisitive crime without taking away the moral culpability of the thief.

As McDonnell said today, "when Pat says something like that, he’s been a politician, he's been around a long while, he knows the way that will be interpreted". His question was in line with the shrill and cynical moralising of many Corbyn critics.

Opposition to Corbyn is often expressed in this haughty way, as if he was some kind of aquatic sea-monster whose tentacles are strangling the British body politic. His critics enjoy the safety of knowing that exile – in parliamentary and media terms – involves being patted on the back by almost everyone else. In truth, it is Corbyn who is in exile, as much now as in his three decades on the backbenches. It's just that he's in exile at the top of the party. You need only take a look at the stream of supportive tweets from Labour front benchers to see how isolated he is.

If you can get over the glee and self-rightousness of much of the press coverage, it's actually a shame that Corbyn's new politics experimented was so short. At the heart of it is a true and honourable proposition: that political parties, if they must exist, should be open democratic cultures. They should not be elected dictatorships in the Blairite mould.

The hatred the public feel for politicians when they see them on TV comes from an instinctive feeling that the person they're listening to doesn't believe a word they're saying. You can spot it instantly: the person saying something they don't believe in because of the party line, or pretending a previous policy didn't exist the second their leader U-turns on it. The principle of electing people only for them to then instantly abandon their own beliefs is bizarre and incomprehensible to most people.

Corbyn tried to change this and make politics grow up a little. He may be wrong about several issues, but he is right to want politics to be more nuanced, democratic and multifaceted. He is right that we have seen modern parties be hollowed out by centralised, highly controlling internal management. And he is right that they no longer reflect or speak to the voters who elect them.

But his ideals have come face-to-face with the reality of the Westminster system. Westminster kills free thought and individuality. It only accepts adversarial two-party politics. You can see it in the physical layout of the Commons Chamber. We don't use the consensual horse-shoe shape of most European countries. We have two ranks of seats, staring at each other angrily, at a distance literally defined by the ability of their inhabitants to wield swords at one another.

The structure of the political system only accepts these ossified structures of political debate. And the press, which is as much a part of Westminster as the MPs are, doubles-down on the process, presenting even the slightest deviation from a leader's views as evidence of a party in chaos and a leader under fire. That coverage carries its own momentum, and eventually it becomes an emotional issue. One need only look at the Blair-Brown years to see how personal, and how completely unrelated from policy, political rivalries become in this culture.

Even the coalition was viewed as a foreign contagion which had to be destroyed. And Corbyn's plans for a new politics were far more radical than that.

Whatever his supporters say, the revenge reshuffle does mark the end of the new politics. And it's a shame that it does.