"When I was about seven, my father told me about the Holocaust,” writes Andrew Solmon in his latest book, Far and Away, just published in paperback. “I knew that we were Jewish, and I gathered that if we’d been there at the time, it would have happened to us, too... I had one more question: ‘Why didn’t those Jews just leave when things got bad?’ ‘They had nowhere to go,’ he said. At that instant, I decided that I would always have somewhere to go.”

The award-winning author’s travel writings from 1991 to today are collected in the book, subtitled How Travel Can Change the World. In richly-textured, deeply-felt dispatches from around the world, he shares the transformational effects of simply being somewhere else.

One of those effects is perspective on your place in the world. “You can’t fit in with people by pretending to be just like they are,” he writes. “You fit in by engaging in a dialogue about your differences.”

“When I was arguing for internationalism in the book’s first publication, it didn’t seem that radical,” Solomon tells me, sounding sad as much as angry. “Now, that position, which seemed so undramatic and middle of the road, is beginning to feel like some last great gasp of idealism about how countries can interact with each other across great distances.”

“Part of my reason for wanting to engage with the world is very high-minded,” he adds. “But part of my reason was also because the legacy of the Holocaust weighs heavily on my shoulders. I wanted to feel like I had friends everyplace.”

The book indeed roams everywhere. Solomon inadvertently cruises a gay goatherd in Ulaanbaatar, hangs with cynical artists in Moscow, unwisely drives a massive white Mercedes through Soweto, South Africa, tours Rio’s drug-infested favelas, explores his roots in Romania, and befriends to the president of Ghana — with bizarre consequences.

“It became front-page news. He got labelled as a gay-rights-supporting president. And the press accused me of swinging the election. If I was going to swing an election, it wouldn’t be Ghana.”

Despite his journeys, Solomon’s insecurity has hardly abated. “Just today, I had lunch with three close friends who are all Jewish,” he tells me. “We happened, for whatever reason, to be eating at very WASPY club. We commented to one another how we can grasp the catastrophic nature of our situation in the US better than other people. We all know you can think you live in a solid, society that can turn overnight into place where it’s impossible to live and you can lose everything.”

Solomon pauses. “It’s almost paralysing to me, that sense. And I think it is a very Jewish sensibility. For all of the expulsion from Jews from this place or this place, but particularly after the Holocaust. Stability is not so stable.”

In reality, the Holocaust didn’t intrude on Solomon’s childhood. Born in Manhattan to an extraordinarily wealthy family — his father headed pharmaceutical giant Forest Labs — Solomon graduated the gilded Horace Mann high school cum laude; at Yale, he achieved a magna cum laude with his English degree. He studied at Jesus College Cambridge, where he received the top first class degree in English in his year, and won the University’s writing prize.

In 2013, he returned to Cambridge to earn a PhD in psychology; today, he’s a professor of psychology at Columbia University.

As he revealed in his acclaimed 2002 memoir The Noonday Demon, he also suffered from crushing depression, and tried to kill himself more than once — occasionally with trips to London aimed at infecting himself with HIV. He’s since recovered, with help from pharmaceuticals and therapy and he’s maintained a 10-year marriage, to journalist John Habich. Dame Julia Neuberger, senior rabbi at the West London Synagogue, married them. They are raising their two kids as Jewish, “though not with enormous religiosity. The mother of my daughter is a Methodist and my husband’s a Catholic. The kids have a strong sense of Jewish tradition and what it means. We go to synagogue on High Holidays.”

Solomon’s a dual UK/US citizen, which — like so much of his life — involves a terrific story. “I had an artist’s visa to work in the UK, and eventually qualified for naturalisation,” he explains. “I met all except the one stipulating that I not have spent more than a fixed number of days outside the UK in a certain number of preceding years. My solicitor thought I was out of luck. But I wrote a letter to the Home Office saying that while I had been abroad both for work — I was then writing a book about Soviet artists — and for family reasons — my mother was dying of cancer — I was, in my heart, loyal to the Queen. I received papers almost immediately, and I was naturalised very soon thereafter.”

The family now split their time between New York and London. “There’s more directly expressed mainstream antisemitism in the UK versus the US,” he says. “The US has plenty of neo-Nazis and antisemites, but I feel the way in which valid anti-Zionist positions bleed into antisemitic positions in England is very disturbing. Antisemitism is more widely accepted in ‘polite’ circles in the UK, whereas in the US, it’s expressed by virulent nationalists. Things feel fragile in both places.”

I ask Solomon where in the world he’d send Donald Trump and Theresa May to broaden their horizons.

“The problem with Trump is that he’s impervious,” Solomon says. “He’s been places, but taken nothing from them. It would be great to send him somewhere like Afghanistan, to notice the plight of people whose lives have been destroyed by wars not of their doing. But he’d probably leave unchanged by the experience. I’d love to send him to South Africa and see how a country that was so ravaged managed to rebuild itself and move past darkness and evil.”

May, he says, is “not as impervious. Maybe she could spend time inside camps for Syrian refugees in Iraq and Lebanon and hear what people have to say. That’s the experience I want her to have — to not dismiss suffering of other people as matter of statistics, but of anguish.”

How can the rest of us to become more active travellers?

“My first advice is to be the opposite of what I’ve described Trump as being,” Solomon says. “He’s impervious — be ‘pervious’, if that were a word. Be as undefended as possible — not against danger, but against your own fear of strangeness.

“Don’t go in with strong beliefs that how your culture does things is better. And don’t assume a place is dangerous because it’s remote and strange.”

He chuckles. “Oh, and take a lot of mosquito repellent.”

Far and Away by Andrew Solomon is published by Vintage (£12.99)