Just before departing for the summer recess, a group of Labour MPs stood on the House of Commons terrace discussing the impending leadership contest.

‘We’re going to have to bite our tongues quite a bit over the next few weeks,’ said one modernising former Labour Minister. By that, he meant they would have to suppress their lingering doubts about Owen Smith – and his efforts to ingratiate himself with Jeremy Corbyn’s Left-leaning base – in a desperate bid to arrest their party’s death spiral.

They can stop biting their tongues now. There’s no longer any need to maintain the pretence. Owen Smith has blown it.

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'Pin-up for mendacity': Owen Smith's performance has been like Frank Underwood in political drama House of Cards

Beating Corbyn was always going to be a tough task. It became an almost impossible task when his disciples managed to circumvent the restriction on non-members voting in the contest, and signed up tens of thousands of ‘supporters’ at £25 a pop. But against a strong candidate, running an aggressive, well-focused campaign, Corbyn could have at least been forced to put up a fight.

Owen Smith is not that candidate. He has run a spineless, incoherent, incompetent campaign.

As a result, Corbyn is shambling along to another victory.

When Smith was selected as Corbyn’s challenger, he was sold as 'clean skin'

When Smith was selected as Corbyn’s challenger – or rather, when he brutally elbowed Angela Eagle aside – his supporters explained to me that he had three big selling points. He was a ‘clean skin’ – ie not one of the usual anti-Corbyn suspects. He was a polished media performer. And he was a tough political street-fighter.

It took precisely 24 hours for Smith’s clean skin to be scarred by the stigmata of Blairism. He had worked as a consultant for ‘Big Pharma’. He had welcomed private sector involvement in the NHS. He had guardedly backed the Iraq War.

His skill as a media performer was demonstrated on Wednesday, when he tried to boast of his pivotal role in the Northern Ireland peace process. When this John Terry-style glory-hunting fell flat, he tried to further embellish his credentials in international conflict resolution by announcing he would happily sit down for talks with Islamic State.

Whereas most Labour politicians content themselves with waving the red flag, Smith opted to wave a black one. An hour later Corbyn’s camp issued a statement distancing themselves from his stance, leaving Smith the only person in British political history to be outflanked by Jeremy Corbyn on the issue of national security.

Questioned about the ongoing bullying and intimidation of Labour members who do not support Corbyn, Smith the dogged street-fighter pleaded: ‘I am not a Blairite, I am a socialist just the same as you. I have never been a Blairite.’

That last exchange perfectly encapsulates Smith’s strategy. His message has essentially been: ‘I am just like Jeremy Corbyn. I believe in the same things as Jeremy Corbyn. Ditch Jeremy Corbyn.’

Amazingly, this ‘Dump Corbyn, Get Corbyn’ line isn’t resonating with the Corbynite true believers. For the simple reason that while many of them are stark-staring mad, they aren’t stupid. This is how Smith thought he could secure the Labour leadership. ‘Jeremy Corbyn’s supporters are very Left-wing,’ he told himself, ‘and I need them to vote for me. So I’ll pretend to be very Left-wing too. That’ll fool them. Then I can start dragging Labour back to the centre-ground, which is where it has to be if I’m going to get to be Prime Minister.’

Corbyn’s camp distanced themselves from Smith's offer to 'negotiate with ISIS'

Owen says he's not a Blairite - he was elected under Ed Miliband

As a master-plan for wooing Corbyn’s supporters into his warm and pragmatic arms, it was utterly brilliant. Except it had one fatal flaw: It was so childishly transparent and craven, every Corbyn supporter in the land knew it was his master-plan.

Maybe Smith did while away the hours at his desk at Pfizer dreaming of the true socialist alternative. But if he did, Corbyn’s diehards aren’t buying it. And nor, frankly, is anyone else. To be fair, when Smith says he was never a Blairite, I believe him. But that’s because by the time he was elected an MP, Tony Blair was long gone. If Smith had been an MP when Blair was leader, he would have been a Blairite. Under Brown, he’d have been a Brownite. As it was, when he was elected in 2010, he became a Milibite.

And now, in 2016, he’s conveniently become a born-again Corbynite – albeit one who can read an Autocue.

Ask any Corbyn supporter why they back their hero and they will cite the same thing – his personal integrity and political consistency. Ask them what they hate about his opponents and they will again speak in unison – their say-anything-do-anything-to-win mendacity.

Smith has made himself the pin-up for that mendacity. So when he launches – as he did last week – an attack on Tory plans to ‘privatise the NHS’, the Corbynites don’t think ‘Wow, there’s the new Nye Bevan!’ They just Google his 2006 interview in which he insists, ‘If private finance initiative works, then let’s do it. What people want to see are more hospitals, better services’, and then think, ‘There’s the new Frank Underwood from House of Cards’.

There is also one other gaping flaw in Smith’s grand stratagem. His message to Labour members is that whatever their ideals, if they want to see them put into practice they must win the next General Election. They have to, in his own words, ‘smash Theresa May back on her heels’.

His message to Labour members is that whatever their ideals, if they want to see them put into practice they must win the next General Election

The problem is, Smith can’t win the next Election. He no more passes the ‘Downing Street test’ – can you picture that person standing on the doorstep of No 10 – than Ed Miliband did. And if he ever tried to smash Theresa May back on her heels, Theresa May would chew him up, spit him out, and parade around the Despatch Box wearing his glasses as a trophy.

Labour members needed to be forced to make a choice. A genuine choice: ‘Do you want to vote for Jeremy Corbyn, or do you want to vote for the next Labour Prime Minister?’ But they haven’t been presented with a choice between Corbyn and the next Prime Minister. They’ve been presented with a choice between Corbyn and a confidence trickster: ‘Do you want to vote for the real Jeremy Corbyn or do you want to vote for a fake one?’

To stand any chance, Smith needed to hurl himself at Corbyn with an unbridled political ferocity. Instead, he has tried to cower and wheedle and ingratiate himself towards the Labour leadership.

There are a large number of Labour Party members who do understand the party needs to win power

Everything Corbyn believes in is wrong, but at least he believes in something. Smith’s convictions appear to extend to repeating everything Corbyn says, then screaming ‘but we need to be in power!’ in an increasingly broad Welsh accent.

What Smith doesn’t seem to understand is that his party is in a fight to the death. And there are only two sides doing the fighting. There are the Corbynite Jets and the Moderate Sharks. There is no longer any hiding place – somewhere where people can cower, meekly trying to keep a foot in both camps.

The hiding place, in other words, that Smith has been trying to find over the past few weeks.

In one respect, Smith is right. There are a large number of Labour Party members who do understand the party needs to win power. Many of them – maybe even a majority – would be prepared to compromise on some of their principles if they thought it would deliver their party a victory.

But what they are not prepared to do is compromise those principles for another defeat.