We Need To Talk About Lionel

And she admits she never wants to become the whingeing ex-pat prognosticating on a home country she no longer understands.

“As well as having family and friends here, I still set books here so I like to keep tabs on what’s going on,” she says. “One of the complications of living outside my own country is it’s very easy to lose track of how people are talking, and of the big political issues.

“A lot of it leaks outside the country but there’s nothing quite like spending a good bit of time somewhere to get the feel of what’s happening on the ground.

“There comes a point where you have to research your own country in the same way you do everywhere else. It’s a big mistake to take for granted that just because you are American you know what’s going on. If you don’t go back, you really don’t know what you are talking about any more.”

Shriver famously wrote about American high school massacres in the Orange Prize winning We Need To Talk About Kevin and her 10th and latest novel So Much For That is a savage indictment of the US healthcare system as a couple spend their life savings to prolong the (terminal) illness of a sick wife.

The 53-year-old says spending three-quarters of her life in the UK gives her work more breadth and means she has “more perspective” on American affairs.

“When you live here, it seems America is the whole world. But when you live outside it, you suddenly realise ‘oh that’s just the way they do things there’.

“Anyone who travels knows what I’m talking about, when you go to another country and culture, even if it’s only on holiday, that place becomes real to you when it wasn’t before, no matter how many books or articles you read.”

As a self-confessed news junkie, Shriver devours American newspapers and TV channels when in the US, and British papers and TV – especially Newsnight with Jeremy Paxman – when at home in London.

“It’s an advantage to follow an entire other set of politics and cultural and social issues up close, to feel involved in them. I have two different channels in my head, two different gears I switch them quite cleanly. When I come here, I stop reading the British papers because I want to enter a different world. Then I go back and read the British papers avidly.”

While she believes the New York Times outpaces any paper in the UK, she thinks our TV steals the march on the US.

“I am a TV news addict and a complete fanatic about Newsnight. I watch the Channel 4 News every night when I am in Britain and I miss certain in depth intelligent TV news that you don’t get over here.”

Shriver has in the past written about Britain. Her third novel was set in Northern Ireland where she lived for several years, and her eighth, The Post-Birthday World, portrayed an American woman living in London who falls for a snooker player.

But she says drily, the resulting criticism didn’t increase her enthusiasm for repeating the experience.

“There are some complications to my setting books in the UK. Readers sometimes ask why I don’t set more books here but you only have to look at the British reviews for The Post-Birthday World to answer that question. The British are very territorial. It seems every writer in the UK feels it’s their God-given right to set books in the US and write American characters and accents and vernacular but Americans are not welcome to set their books in Britain and if they do, people will go over them with a fine toothcomb and try to find so-called mistakes. It’s quite off-putting.”

This brings her onto the insidious xenophobia she encounters as an American author in this country.

“Americans are in general less sensitive to people writing about them than most other nationalities. They are being penetrated by other cultures all the time and you don’t get this ‘go back where you came from’ thing over here. Someone like me who has been a denizen of Britain for decades, if I had lived here for that long, I would be a New Yorker, but in London I have that feeling that never quite goes away that I am an outsider and that everything I say is being filtered through my accent.

“I feel I have to watch my back, which I hardly ever do and there are limits to my inclusion in the so called literary community.”

She sighs that her character lacks the deference and politeness that we British revere: “My problem is I am not a very polite person and I am constantly putting my nose into your business and it does alienate people.”

So why settle in the UK?

“Habit, laziness. There is an element of sheer accident in my ending up there. Most of life is accident. It’s possible that in the fullness of time I will return to the US for my decrepitude but I know I would miss Britain. I find when I entertain the notion of the life I would lead if I was just back in the US, it suddenly feels very much smaller.”

It was the death of a close friend from cancer and musing over her own future that inspired So Much For That. As a British tax payer, Shriver has a “visceral relationship” to issues such as the funding of the NHS.

“There is only passing reference to the British system in the book but the politics that informs it are all to do with my having lived in Britain and having a perspective on the way people do things here. I have been exposed to a system which for all its flaws, works better than the chaos we have over here.”

Characteristically, Shriver has strong opinions on our national healthcare system. She admires the way that Nice (The National Institute for Health and Clinical Excellence) takes “incredibly painful decisions” about what should be funded rather than leaving it up to the kind of insurance you have or what you can afford.

And she believes the NHS will have to shrink its “core mission”, no longer funding non essential gender realignment or fertility treatment.

But for all its specificity, she hopes So Much For That touches on more universal emotional and political themes

“I have audiences all over the world and even if I set a book in the US I am trying to write something that has relevance to other places. All of our health systems are under strain because of ageing populations and escalating technology. We can’t keep spending an infinite amount of money on health and there are a lot of drugs out there that benefit virtually nobody. That’s the sort of drug I don’t think the NHS should be funding.”

Shriver’s most successful book to date, We Need To Talk About Kevin, she says was successful, not because it was about a school massacre but because “it’s talking realistically about modern parenthood and a woman’s experience of ambivalence on deciding whether to become a mother.”

“When things go wrong between parents and children it tends to be adversarial, not usually as extreme as it is in that book but it clearly resonated with people.”

o Lionel Shriver is in discussion with fellow American novelist Tracy Chevalier at the Hampstead and Highgate Literary Festival at Ivy House, Golders Green on September 20.