On 26th September 2007 David Cameron gave what he called a cast-iron guarantee. The guarantee appeared in a piece published under his name in Mr Murdoch’s Sun. Liberal Democrats, who set some store by their own political education and haven’t read the piece, really should take the opportunity to read it in its entirety.

The aspiring party leader explains that it is an article of faith for him that: “No treaty should be ratified without consulting the British people in a referendum.” And, because of that, he promises, any Conservative government led by him will “hold a referendum on any EU treaty.”

Mr Cameron explains, in the same piece, that his determination to hold a referendum isn’t simply a reflection of his deepest political beliefs but a practical matter too. It is integral to Conservative economic policy making. Why should that be? The explanation seems straightforward. It is vital because: “One of the great challenges [facing the UK is] rolling back the tide of bureaucracy.” And, Mr Cameron continues, “you can’t do that without targeting one of the main sources of this bureaucracy – Brussels.”

Without the referendum he’d promised Mr Cameron makes it clear it will not be possible to free UK businesses from red tape; the kind of European regulation which makes it impossible for the UK economy to succeed. Of course what most of us call regulation – and Mr Cameron calls red tape – isn’t quite the easy target that it once was. And Mr Cameron’s cast-iron guarantee has almost completely rusted away.

Just two years after giving his promise the Tory leader – who distinguished himself from Gordon Brown before Sun readers because of his own principled stand on the Lisbon Treaty – is about to dump his absolute commitment on the Treaty.

Sun readers and Conservatives – not quite the same thing – are not the only ones who are entitled to ask: “What does a cast-iron guarantee from Mr Cameron add up to?” However, some of those you might have expected not to have been easily taken in by a Cameron promise – such as Tory MP Bill Cash – still don’t appear to get it. Mr Cash insists that Mr Cameron’s promise is…well…unbreakable; there can be “No ifs no buts”.

Mr Cash continues to tell The Daily Telegraph: “We need a full referendum on Lisbon as we were promised.”

Of course Mr Cash would do well to talk to Mr Cameron’s closest associates, the ones who recently made it clear to Financial Times reporters Jean Eaglesham and Alex Barker that: it is unfair “…to hark back to remarks in an interview with the Sun, as [Mr Cameron’s] pledge [needs] to be seen in the context of the expectation then that a general election was likely in weeks.”

So what should we expect a principled and tactically astute Conservative leader to do? Whatever it is it is unlikely to be what Mr Cameron does. Sources close to the Tory leader are already letting it be known that a Conservative manifesto promise to negotiate opt outs for the UK from EU social and employment law will be pursued pragmatically. What – you might ask – does that mean?

Eaglesham and Barker were alerted to a Tory strategy that would ‘hijack’ the process of Croatian accession to the EU in 2010 and 2011. The plan: to use Croatian accession as a lever to extract concessions capable of being packaged and presented to the British public as evidence of unqualified Conservative determination to put British interests first in Europe.

Anyone who doubts that David Cameron is Blairlike and Blairlite should be encouraged to go and read not only the cast-iron guarantee given to Sun readers in September 2007 but Mr Cameron’s carefully crafted denunciation of Labour rivals. Without a hint of irony, Mr Cameron declares that disingenuous British politicians are responsible for spreading a ‘cancer that is eating away at trust in politics’. And, for those who make it to the end of Cameron’s September 2007 serving to Sun readers, there is a closing offer, new politics for old; an offer that would surely put most snake oil salesmen to shame.

* Ed Randall, a Liberal Democrat councillor in the London Borough of Greenwich from 1982 to 1998, edited the Dictionary of Liberal Thought jointly with Duncan Brack. Ed lectures on Politics and Risk at Goldsmiths University of London and has recently published Food, Risk and Politics (Manchester University Press – 2009). Read more opinion articles by Ed Randall