If society’s shakers are divided between insiders and outsiders, Sir Christopher Meyer is more insider-ish than a langoustine snug in its shell. Whenever something creates big waves — the Euro rocks that sunk John Major’s premiership, President Bush’s war on terror, even Britain’s Olympic bid — Meyer is right in the thick of it.

He has shaped important headlines but the name “Meyer” is much more likely to appear in documents marked “top secret” than any newspaper; like all crustaceans, he prefers to swim in the dark leaving the bright lights of publicity to lesser mortals. He was, then, a natural to become the discreet power behind the news, chairman of the Press Complaints Commission, which is entrusted with keeping journalism in some kind of self-regulating order.

“Establishment” is the word that leaps out at you when describing Meyer (Lancing, Cambridge, Foreign Office). He is so smooth he glides across his brief like a billiard ball on green baize. Having been Major’s official mouthpiece, the Alastair Campbell of his day, he moved effortlessly to work for Tony Blair as our man in Washington (jealous rivals love to say he was schmoozing Labour before John Major breathed his last prime ministerial gasp).

Meyer must know where more bodies are buried than an undertaker at the Somme. No wonder leaders value his counsel, and his cunning (Dubya Bush invited him to dinner before he left Washington; Blair had him down to Chequers the other day). He is truly on the inside loop.

How Blair must have regretted Meyer, 59, deciding not to front Britain’s Olympic bid: I can just imagine Meyer masterfully — and discreetly — twisting dodgy dictators’ arms to get our bid backed.

We talk of his sojourn in America. Nobody forged the Bush-Blair alliance more than he, riding into Texas to woo Bush even before Dubya sought the Republican presidential nomination. He must have feared Bush and Blair would make an incongruous couple. “I can understand why you might think that. But Bush was pragmatic, no pomposity. I was the most confident because I was the only person at the senior level who knew both men. The Americans didn’t know Blair, and No 10 didn’t know Bush. A lot of people had anxieties.”

He fought hard for British interests in Washington. “I banned the term ‘special relationship’. I didn’t want my staff to think it obeyed some other law of foreign relations that meant they didn’t have to do any work,” says Meyer.

It is easy to see what America got from us over Iraq but how are what he terms our “hard interests” served in this bargain? “We should think conceptually of a single transatlantic community,” he says. “People ask, ‘How can you say there is no choice to be made between Europe and America?’ But that is the wrong question: a majority of European countries were with us (on Iraq). It is not ‘Can Blair continue to ride two horses?’ but whether part of Europe can come on board with the rest of us.”

Dexterous rhetorical footwork, but it doesn’t show how the Lutyens mansion housing our Washington embassy earns its keep. Did he have real leverage, or was he a grand fig leaf for American power? “You have real leverage to mould or amend American policy.”

The flowering of the Bush-Blair alliance on terror, he says, took place when the Coldstream Guards played the Star-Spangled Banner after 9/11 at Buckingham Palace. “You cannot believe the reaction: the phone calls we had with people breaking down to weep. I have yet to discover who the genius was who said, ‘Let’s play that today’.”

That grief was turned into a joint assault on Iraq. How important is it to find weapons of mass destruction? “The intelligence I saw left me in no doubt Saddam Hussein was involved in concealed programmes. The notion we went to war on a fraudulent prospectus is quite wrong.”

When Meyer makes a slightly implausible argument, he sounds incredibly authoritative, particularly with his slight David Frost drawl. It is easy to see why Major relied on him, but it must have been grim in that bunker. “Whenever he looked like crawling out of the mire, his own party would drag him back in,” Meyer admits.

Alastair Campbell, has been accused of debasing public life with spin. Fair? Apparently not: