A brand new set of turnstiles has just been installed at the Scottish Parliament. They are an up-market version of the kind you find at football grounds, except that here they are in gleaming Perspex, operated by a swipe card, and cost £300,000. They were put in, I can reveal, on the recommendation of a body with which I was unfamiliar, called the Centre for Protection of National Infrastructure.

By remarkable coincidence, yesterday was a day when everyone at the Scottish Parliament seemed to be bidding to protect the National Infrastructure. Alex Salmond, Cromwell-style, presented himself as Lord Protector in Chief, telling the Parliament about his sterling, if unsuccessful, efforts to save the jobs of workers at the Diageo plant in Kilmarnock. He had even marched alongside them to protest at the closure plans.

“Not only will I never apologise for standing shoulder to shoulder with a workforce in their time of extremity,” he proclaimed. “I am proud of a country and a community that cares enough about their company and their product to rally in defence of jobs in Scotland.”

Some of us wondered whether this was not more Arthur Scargill than conciliator in chief, but Mr Salmond did not get where he is today by staying detached.

“Diageo as a company have been focused on what they can save in terms of cost, on what they can maximise in terms of profit,” he thundered. “I believe there has been little or no focus, until late, in terms of the social consequences of their economic decision-making.”

Shock, horror! First Minister reveals that companies try to save money and make profits. Whatever next. Iain Gray, the Labour leader, could not quite match this. But he did think that Mr Salmond had been less than statesmanlike in his dealings with the company.

“I read this morning widespread criticism of the First Minister for megaphone diplomacy, for grandstanding, and for choosing a TV appearance over a meeting with Diageo’s chief executive,” he said. “Wasn’t the First Minister part of the problem, not the solution?”

If he had stuck to this point, Mr Gray might have made some progress. But he chose instead to widen the attack by referring to a leaked civil service memo which took us into arcane areas of public policy —- the kind that you attend day-long seminars about.

Mr Salmond was withering. He attacked Mr Gray for moving from serious subjects to “politicking” — a concept with which he himself of course is quite unfamiliar. To underline the point, he described Labour as a “lap-dog of Westminster”, tied to the “apron-strings” of the Treasury’s financial settlement.

I do not wish to strain the analogy, but once again, the overtones of Marxian invective were unmistakeable.

Was this really our First Minister or someone from the Scargill school of dialectical materialism? On occasions like this, Mr Salmond likes to turn around and address the Labour benches as a body, almost as if he has called them in for a disciplinary hearing. Watching their faces, you can see why. Some of them fiddle furiously with their notebooks, others attempt to answer back, some of them simply look mutinous.

By this stage, the Presiding Officer had begun to complain that far too much time had been taken up already with these exchanges, and that backbenchers should be given a chance. Mr Salmond was unimpressed. He continued his stern lecture, telling Labour MSPs in no uncertain terms that the reason the country was in such a poor financial state was because of their government in London, and that they would have to explain to the electorate why Scotland had been short-changed by £500 million, with the result that budgets might have to be cut by 11 per cent. If that happened, it was entirely the fault of the Labour Government “at Westminster”.

One might have expected furious shouts of “rubbish” or “shut up fish-face!” Instead, Labour MSPs looked almost shame-faced. Perhaps those new gates are meant to prevent them escaping rather than trying to get it.

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