He has now found his correct niche as arguably the most agreeable voice on radio (Off the Page, Friday evenings, Radio 4) and award-winning (most recently, the George Orwell prize) columnist for The Times. As a gay political commentator, he was exactly the man to out Peter Mandelson on television.
Yet back in the Seventies, the Foreign and Commonwealth Office (FCO) seemed to be just what the careers master ordered. Born and brought up abroad, he got a first at Cambridge and he got drunk at Yale.
"I felt British," he says, "and I was interested in politics." As his "insurance", he already had an offer from MI6, but, unlike the spymasters, he realised that he would not have been much use as a spook. "Gay spies do not have a good record."
Fortunately, the FCO job materialised and for two years he learnt the ropes among the phenomenally bright pullers of international strings. Working in Whitehall's Western European Department, he kept an eye on Scandinavia and Italy.
"The Foreign Office taught me about tight drafting, a Rolls-Royce of a skill." He drafted jokey speeches for the then Foreign Secretary James Callaghan and put amiable words into the Queen's mouth when she was welcoming a Nordic bigwig to Scotland. Yet he left after two years.
"I hated the Foreign Office," he wrote in his very funny autobiography, Chance Witness. "I hated it with a slow-burning, fiery passion." It was the emphasis on style rather than substance which got his goat. No one bothered if a report was right but how its pages were held together. "Paperclips were vulgar, what they used at the Department for Health and Social Security."
Stapling was unsound, too. If pushed, pins were permissible, so long as they were inserted from top sheet to bottom sheet, then back to top sheet. Finally, the points could not stick up in case they pricked a minister's finger.
Then there was the sofa regulation for junior FCO officers at social events. They should not take a seat next to a senior officer or a senior officer's wife, nor should they sit down next to an empty seat which might be occupied by a senior or senior's spouse. One day he noticed an advertisement on the No 88 bus: smart lad wanted as apprentice diesel-fitter at a London transport garage.
He saw this as a way out and, via the trade union activism it could involve, an unorthodox entry into the ranks of Conservative MPs. London Transport rejected him but, finally, he resigned anyway.
Yet he does not totally dismiss the FCO as a career. "If you are prepared to go through the hoops in the right order, it's really high-calibre, really high-octane," he adds - diplomatically.
A Castle in Spain by Matthew Parris came out last week (£17.99, Viking)Reuse content