This is Peter Hitchens' Mail on Sunday column

I recently visited a ‘head shop’, one of many totally legal establishments now flourishing on British high streets, where users of officially illegal drugs may buy the equipment they need to enjoy their criminal habit.

I didn’t buy anything. But one of the items on sale was a wall-clock, especially designed to be used to store drugs. ‘Hide your stash in plain sight!’ said the little poster next to it.

It is good advice. If you really want to conceal something, leave it lying about where everyone can see it.

This is what the Prime Minister has done with his supposed promise to hold a referendum on British membership of the European Union.

The dishonest trick at the heart of the offer is so blazingly obvious that nobody notices it.

Let me explain. If Mr Cameron really believed that he would win a parliamentary majority on May 7, he would not make this promise.

He loves the EU so much that he has said that he wants to extend it to the Ural mountains. He absolutely does not want this country to leave it.

But because Mr Cameron knows perfectly well that he will not win such a majority, and that no possible coalition partner or ally would support such a referendum, he feels safe to make a pledge that will never be redeemed.

The purpose of the pledge is to win back some of those voters he and his Blairite friends have long derided as fruitcakes and closet racists. He despises them, but he wants their support to ensure that the Tories are the largest party, and that he stays in office.

It would be disastrous for him if they all took him too literally. He needs some of them, but not all of them.

This is perhaps why the Tory Party’s campaign is so crude, narrow and awful, almost designed to repel thinking and decent people.

The interesting thing about all this is that it is so blatant, yet nobody seems to notice it, just as they don’t notice the perilous state of our economy (another disastrous balance of payments deficit was announced last week). And just as it is obvious that, while we are supposed to have ‘tough’ and ‘draconian’ laws on drugs, shops which help people take drugs thrive all over the country. I sometimes wonder if, one dark and tear-stained morning, all these many lies will be brutally exposed in one dreadful awakening.

Winning at any cost? It's the only Game in town

When I rather guiltily read the books on which the TV series Game Of Thrones is based, I was struck by one thing. The whole point of this saga is that ruthlessness pays, that evil generally wins, that justice is non-existent, and utter cynicism the only wisdom. It is the Middle Ages without the saving grace of Christianity.

The whole idea is symbolised by the ghastly Iron Throne for which the various factions and clans compete, and which, once gained, eats into the souls of all who sit on it.

I won’t watch the TV version because I very much do not want to see a slick and well-acted portrayal of such foul behaviour. But the success of this drama suggests that this sort of merciless immorality now has a wide and receptive audience. Gleeful, unembarrassed ruthlessness, once rightly kept in check, has become normal among us, and Game Of Thrones is a success because this change is now more or less complete.

Political campaigning has played its part in this. I first noticed really dirty tricks in the 1997 campaign, when New Labour screened a particularly vile anti-Tory broadcast personally mocking Tory politicians and conference representatives, and falsely alleging a plan to ‘abolish the old age pension’.

Once, this sort of thing was left to underlings and backstairs-crawlers who could be disowned. But now it seems to have become central. The Defence Secretary, Michael Fallon, is a senior Cabinet Minister and an experienced grey head in the Tory Party. I rather like him. But his outburst against Ed Miliband, accusing him of stabbing his brother in the back, and planning to do the same to the country, was a departure from the old rules of gentlemanly combat.

It was also inaccurate, as Mr Miliband stabbed his brother in the front, openly campaigning against him in an election – more than can be said for the Tories, who deviously overthrew Iain Duncan Smith in a cruel and personalised putsch.

But perhaps the most tricky and ruthless political act of the week came from the Blair creature, who ‘supported’ Mr Miliband on the European issue. How can this ghastly, discredited man not know that his kiss is the kiss of death? Of course he does.

Compared with Blair’s embrace, a stab in the back would be an act of kindness.

You shouldn't make it up

The story of how the young Princess Elizabeth and her sister Margaret mingled incognito with VE Night revellers is a moving and very British episode.

So why must the makers of a new film, claiming to be about the event, fabricate falsehoods about the King’s daughters going to brothels and gambling dens, and Princess Margaret getting drunk?

I suppose that having got away with the multiple untruths in The King’s Speech, the movie industry felt that invention was better box office than truth.

And yes, I know Shakespeare made things up, too. But this stuff isn’t Shakespeare.

The devastating attack no one heard

In a grown-up campaign, last week’s attack on David Cameron by a former British ambassador to Syria would have been devastating. As it is, it seems to have passed almost without notice.

Here’s a flavour of the indictment levelled by Peter Ford, Our Man in Damascus from 2003 to 2006. ‘If Cameron had his way, the jihadists could have been in control of Damascus by now,’ and, ‘To call for the overthrow of the secular Syrian government, to demonise it out of all proportion… to predict its imminent fall… and then to wail as though it was nothing to do with them when British Muslims set off to help hasten said overthrow is inconsistent and nonsensical.’

I couldn’t agree more, and still can’t understand how he gets away with it.

Meanwhile, Mr and Mrs Cameron go around the country eating bacon sandwiches and hot dogs with knives and forks to avoid embarrassing photos.

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