‘VENI, Vidi, Vici” – “I came, I saw, I conquered” – is attributed to Julius Caesar. However, with regard to Jeremy Corbyn’s visit to Scotland it was more a case of “he came, he saw, he failed”. In a TV interview earlier this week he was asked six times whether he believed Britain would be better off outside the EU and six times he failed to answer, a failure symptomatic of his leadership.

Brexit is the single biggest political issue of our time. Sterling has crashed, standards of living have declined and the future prosperity of the many, though not the few driving it, are threatened. The Government is belatedly making contingency plans for a No Deal Brexit the likes of which haven’t been contemplated since Dunkirk was evacuated or nuclear oblivion contemplated, and an election may very well be brought about by it.

So it’s not something to prevaricate on. But what was given was fudge and waffle. “I want to have a good relationship with the EU. That’s what we have to have in order to maintain jobs” was the response. Just what does that mean? Even ardent Brexiters aren’t arguing for a bad relationship with the EU, they simply “want to have their cake and eat it”. to paraphrase their new de facto leader Boris Johnson.

There are also two other factors. First, Mr Corbyn supposedly voted Remain, in line with Labour’s official stance. On that basis you’d suppose he might have said that Brexit wasn’t his preferred position and there would be consequences which he’d seek to mitigate. Instead there was only obfuscation confirming the view of many that he’s always been a closet Brexiter, and was as active in support of the official Labour position as Theresa May was loyal to David Cameron.

Secondly, he’s the alternative Prime Minister, not some humble backbencher. Indeed, had the last election run on a week longer or the Grenfell tragedy occurred slightly earlier he could very well have been occupying 10 Downing Street at the moment. So it’s not a question that he can dodge because of its importance and his position. But he did and frankly it was pathetic.

I’ve been prepared to give Mr Corbyn a fair wind. I thought his election campaign last year was refreshing and his conduct then was exemplary. He captured a mood across the land wanting change and displayed great dignity when attacked mercilessly and often unfairly.

I’ve stood by him over anti-Semitism claims where I think accusations against him are totally unfounded, even if his handling of the issue has been found wanting. I’ve even sympathised with him when he’s found himself isolated and been attacked by many of his own MPs.

Despite my doubts that he knew or cared little for Scotland, possessing little idea of life outside the M25 corridor, I was prepared to cut him some slack. But it’s more than two years since the Brexit vote and as we’re reminded daily the clock is ticking and it’s more than a year since he was empowered by the election result. So, not any more. He’s not just failing in his leadership but fading in his political positioning.

During the Scottish visit he went to Edinburgh Book Festival, sharing a platform with Yanis Varoufakis, another darling of the Left. Fist bumps were exchanged between Mr Corbyn and with the former Greek Finance Minister but there’s a chasm between them on Brexit. The latter has written and lectured on “international socialism, not socialism in one country” and argues against Brexit. The former on the other hand seems to want Brexit, despite weasel words about a “jobs-based Brexit” or vacuous statements on a “customs partnership not customs union”. Mr Varoufakis is seeking unity on the Left and working within the EU, but Mr Corbyn is espousing “socialism in one country” first advocated by Stalin and that’s failed wherever it’s been tried.

The freshness that Mr Corbyn once brought has long since worn off. It’s not just Britain but the world that has changed and he’s still stuck in a time warp. There’s no new vision that the Left so badly needs. Instead it’s to be a siege economy and policies from the 1980s, if not the decade before. Jim Callaghan’s Labourism and Michael Foot’s socialism both failed and the world has moved on with globalisation.

I share Mr Varoufakis’s fears over the future of socialism, as the social democracy I support collapses all across Europe, yet his solution offers more hope than Mr Corbyn’s.

Meanwhile, the party he leads is bitterly divided and incapable of working out what its position is on almost every major issue. The old political adage that the opposition is across from you but the enemy behind you seems to have been written for the Parliamentary Labour Party. It’s not just in Westminster where the knives are out with MPs refusing to serve in his cabinet but in Holyrood, where the majority of MSPs supported Anas Sarwar, not Richard Leonard.

What’s the party stance on anti-Semitism? Is it that of Margaret Hodge and her allies or Mr Corbyn and his? Who speaks for Scottish Labour? Is it Richard Leonard or Ian Murray, as on critical issues they often seem diametrically opposed? Who’s Lesley Laird and what’s her purpose?

The sojourn north was a chance to reset the dial on the constitutional issue, as Labour seeks to win back support haemorrhaged during the independence referendum. Suggestions were made a year ago that new pronouncements on federalism were to be anticipated. Well, we’re still waiting and whilst he’s never equated Holyrood with a parish council like Tony Blair, his support for it is as lukewarm and insincere as his commitment to Remain.

His failure is a tragedy for the entire country. Not just the most incompetent Government but the most odious administration in living memory could well be returned, with the leader even supplanted by someone worse.

Labour should be able to offer salvation, instead it is almost unelectable and offering no alternative on the critical issue. Thousands chanting his name doesn’t bring socialism. Credible and coherent policies are required.