The one thing I have always tried to pack when travelling is manners — but I’ve learnt to my detriment that the desperately “British” urge to be polite can be burdensome, if not downright perilous to all involved.

On my first visit to New York I was by myself at a large table at 9 Irving Place in Gramercy Park, eating angel hair pasta with pesto, when Andy Warhol and his retinue swept in and sat down by me. “Hey, he’s English!” they shouted. I was trying to sound intelligent about the New York art scene when Warhol, smiling sweetly, pulled his boyfriend’s bare arm into the candle flame and held it there.

I watched speechlessly as the screaming youth was led away to the nearest burns unit. What was the right thing to say? Could I have stopped it? In the silence, the artist gave his little laugh and said: “Well, after that little drama we must all have the crème brûlée.”

In Paraguay I accepted a lift to the wilderness area of Gran Chaco, home of the jaguar. My guide and his friend began to talk passionately about cats, gatos, in Spanish. I pondered in silence how moved I was that two such vicious-looking men could be so concerned with their nation’s wildlife. When they turned me out in the middle of nowhere after demanding all my money and my cowboy boots I realised they had been talking about gastos — expenses — not gatos.

I still feel very guilty about an incident in Nicaragua during the anti-Contra war. I was invited to the house of a delightful Englishman who supplied the nation’s currency and had three dry swimming pools full of worthless córdobas. As an internationalista volunteer I was due to go to the battle front the next day and was somewhat preoccupied. But all evening he insisted that he was about to be murdered.

“They’re killing everyone. It’s a war,” I remarked in solidarity, but he continued. “Dear boy, I am in mortal peril.” I should have informed someone, but I didn’t want to make a fuss. When I got back to Managua I was told he died that same night, after “drowning” in his waterless pool. His friends said that it was poison.

When I was diving with a Tobagan friend off his lovely island, he found a hawksbill turtle that would feed his family for several days. I was still puzzling how to raise the conservation aspects of hauling it on board when the New Hampshire millionairess who had hired him said that she was not coming on board again unless the turtle went back to his friends. “And you should know better!” she yelled at me.

Managing the right words can flummox the best. In her youth the Queen fed a doe called Daftie at the Balmoral kitchen door. Alas, at Princess Elizabeth’s first formal shoot who should come running towards her but . . . lost for the right words, she followed form and pulled the trigger.

I know that Daftie moment, Ma’am. At the end of the Universe an Englishman, or woman, will still be dithering over whether it’s the right moment to speak up.

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