A lot of people would jump at jobs paying £40k a year

Ravenscraig revisited. Industrial vandalism. Shell-shocked workers leaving factory meetings; self-important union leaders making threats they can't deliver; attention-seeking politicians making portentous pronouncements that only confirm their impotence.

And it's hardly surprising internet conspiracy theorists have been at work construing this episode as a strike against the Scottish independence cause. Well, didn't the announcement come just days after Alex Salmond's rousing conference speech? And just one day before the Dunfermline by-election? Something fishy there, surely. Grangemouth wasn't even raised at Prime Minister's Question time! If this had been a plant in England... etc.

But anyone who thinks Better Together, or David Cameron for that matter, have the slightest influence over the business decisions of Ineos, then they are living in a cyber-fantasy world. Not even the Tories would play politics with one of Britain's biggest industrial concerns. The politicians, Mr Salmond included, are as much on the sidelines of this episode as the punctured balloons of Unite.

This is a very different company from British Steel, British Leyland or even Grangemouth's previous owners, British Petroleum. The key is in the name. They were considerable British institutions, who felt a certain responsibility to their country of origin - or at least pretended to for the sake of their public image. Grangemouth is now in the hands of a relatively obscure private equity company with one of those nonsense names, Ineos.

It is a company led by Swiss-based billionaire James Ratcliffe, who would be one of Britain's richest men had he chosen to keep his money here. He is the nearest we have to a Russian oligarch and his company owns the Grangemouth refinery in partnership with a state-owned PetroChina, which is probably more interested in exporting British expertise to China than in furthering Scotland's industrial recovery.

In other words, this is a very 21st century dispute, involving a global company with a complex ownership and financial structure that keeps its cards close to its chest and doesn't care what anyone thinks about it. We don't even know whether or not Grangemouth is actually losing money. Ineos claims it is losing £10million a month, but others say the company made a £7m profit last year. Tax expert Richard Murphy says they have been making even greater profits through financial jiggery pokery. Ineos is a multinational with operations all over the world and, since it is not listed on the stock exchange, it is very difficult to follow the money.

However, there is no doubt the petrochemicals business in general is under a great deal of competitive pressure right now. In part, this is because of the shale oil boom in the US, which has led to a collapse in prices (not that you'd know it at the pumps). No one believes margins in this global industry, which now also includes highly efficient and low-cost Asian players, are healthy right now. Anyway, the clearest answer to those who believe Ineos is hiding its profits is the fact it is willing to close Grangemouth at a stroke. If there was good money to be made there, Ineos would be digging in - especially with the offer of £300m from the government to modernise the place. This isn't brinkmanship but a bluff called.

And yes, many will criticise the union for not seeing it coming. The workers at Grangemouth are not like the steel workers or factory workers of the 1980s - most earn more than teachers and many other professionals and have final salary pensions to boot. In 2008 they faced down Ineos over pensions, while 700 Grangemouth contract workers supported wildcat action at the Lindsey oil refinery over the employment of foreign workers by Total. British jobs for British workers, they said. Not any more they aren't.

Then there was the farce over the Grangemouth union official embroiled in the Falkirk Labour candidate selection row, which I don't intend to explore here. Suffice to say Unite's attention may have been elsewhere when the crunch came at Grangemouth. Ineos was clearly not bluffing, and the union should have realised that before the liquidators were called in. Now they won't have any pensions at all.

I am not apologising for Ineos. It's behaviour has been brutal. But look: that's what private equity companies are like. They are not called pirates for nothing. Don't expect they will respond to public pressure, or that Mr Ratcliffe is remotely concerned about having the First Minister ringing him up on his yacht in the Mediterranean whence the Ineos boss is reported to be conducting much of his business. He may have been looking for an opportunity to close Grangemouth all along. He may not. We'll never know.

The importance of this plant to the Scottish economy, however, can hardly be over-stated. Grangemouth is not just 1400 jobs, and 8% of Scottish GDP, but the key to the entire energy economy based on the North Sea oil fields. I'm sure Mr Salmond would like to march in and nationalise Grangemouth, like Prestwick Airport. But this isn't some loss-making regional airfield, but part of an integrated, world-wide business with a complex supply chain and owners, including the Chinese, who might not want it to thrive in (Scottish) state hands. You might nationalise Grangemouth at great expense and find that all you have is a lot of pipes.

Clearly, this is a massive threat to Mr Salmond's prestige since he was all over the Grangemouth issue last week, like his icon, Harold Wilson, mediating in a industrial dispute in the 1960s. Yesterday's abrupt closure was a body blow and may be crucial in today's Dunfermline by-election. Of course, Mr Salmond has to do what he can. He still sounds remarkably confident, insisting "contingency plans" are in place for a possible takeover. The refinery itself is, we are assured, being kept operational by Ineos which is good to know.

But I wouldn't put my money on Grangemouth's future. It must now be regarded as a limping industrial casualty, rather than one of the leading industrial sites in Europe. Maybe foreign buyers can be found. But this may not be easy, since Ineos is just the kind of outfit that might have looked on Grangemouth in the past as a distressed asset ready for the picking. The fact it's walking away will frighten off other interested parties.

Clearly, if Grangemouth is to be saved it is going to require the abject humiliation of the union. They are basically being told workers can keep their jobs if they accept a two-year wage freeze and lose their final salary pensions. Well, there are a lot of people who would jump at that in exchange for jobs paying £40,000. It would not be wise to opt for no jobs just to avoid a loss of face. The most important quality in a general is the ability to recognise when you are beaten.