That he knows it isn’t yet just about the acting is made clear when he tells of the time he was taken to tea at Elizabeth Taylor’s. “Elton John had invited me to a luncheon, at which he then said, ‘What are you doing later?’” Er, why does he think Sir Elton wanted to meet him in the first place? “I don’t know,” Ryan Phillippe admits, colouring slightly. “I didn’t ask. I think he’d seen a couple of films and hopefully he liked the work.” There is a pause. “Or maybe he just thought that I was cute.”

Let us concentrate on the body of work. One of Hollywood’s new golden boys, Phillippe is best noted for his work with directors Robert Altman (in Gosford Park), Paul Haggis (the 2005 Best Film Oscar-winner Crash) and Clint Eastwood (the Second World War drama Flags of Our Fathers). But yes, there’s also the cuteness thing. At 33 – he looks younger – this father of two (he and ex-wife Reese Witherspoon have a daughter Ava, aged eight, and a son Deacon, four) is as handsome as any Bruce Weber model and that seems to be hard for many people to get past. For them, accordingly, cuteness remains his defining characteristic.

A young star undervalued as a result of their good looks? In the greater scheme of things, it is not one of the major injustices of the age. But having watched his impressive leading man turn in the forthcoming Iraq war feature Stop-Loss, I have to say that it is at least a pity and that reassessment is overdue. His all-American male beauty and that union with Witherspoon may have made him a gossip column staple, but here is a significant talent, one deserving of recognition.

The two were introduced in 1997 at her 21st birthday party, Witherspoon famously telling him, “I think that you’re my present.” They married in the summer of 1999 and stayed together for seven years, but are now divorced. Phillippe has never spoken publicly about the reasons for their break-up and is currently extending the same policy of polite but determined evasion to any question relating to a rumoured close friendship with one of his Stop-Loss co-stars, Abbie Cornish (while Witherspoon’s name has recently been linked with that of another actor, Jake Gyllenhaal).

He readily admits, however, to having been unprepared for the degree of attention a high-profile romance brings. “I fooled myself into believing it would be easier than it was. To have people speculating constantly about the state of your relationship, casting aspersions and telling lies... It took more of a toll than I was immediately aware of. When you factor in being separated so much because you’re working in different places... Not that I blame our no longer being together on that one thing. I take responsibility and she [Witherspoon] would also for the way we ended up going. But it didn’t help.”

However, the attention has not abated since their parting, due largely to his own rising stock in the film capital. Phillippe regrets this for himself, but nowhere near as much as he does for his daughter. “She’s aware and it creates in her a lot of anxiety, which is partly my fault. When Ava was very young, I was young too. And brash. I’d get... I wouldn’t like to say violent, but visibly angry at the paparazzi back then. She was my first child, and my instinct was to protect her. I remember one time that I’m not at all proud of, I was holding my daughter and handed her to Reese and ran off to chase this one guy down and hit him. I would never do that now.

“I think the attitude I had at the time did create in her a lot of the fearfulness she has today.” His son Deacon is not affected in the same way. “Mainly because since his birth I’ve realised that you’ve got to make it seem like less of a big deal. Ava to this day, though... It breaks my heart to think about it, hearing her say, ‘My friends at school saw a picture of me in a magazine and they made fun ’cos I was carrying a blanket.’ A little girl having to consider how she looks before leaving the house? I have a privileged life and hate to complain but there’s something vile about that.”

With paparazzi attention remaining a fact of his daily life, Phillippe says he is now trying to turn it to some advantage. He has started wearing T-shirts bearing the online addresses of charities he supports (www.childrensdefense.org, for example, or www.africare.org), “because these pictures go around the world and untold numbers of people see them. One organisation told me their web hits went up 2,000 per cent overnight after one such image was syndicated.”

When I remark that I have never been to his home state of Delaware and ask him to tell me a little about it, Phillippe chuckles. “You probably never will go. Not that many people do. But let’s see... It was the first state to ratify the Constitution. It’s the second smallest, with a population of just 840,000 or so. I suppose what’s most interesting about it is its proximity to other places. I grew up 20 minutes from Philly and 40 from Baltimore. New York and DC were two hours away by car.

“So while there’s a lot going on all around, Delaware itself doesn’t have much of an identity. And I’d draw a parallel there with myself in the regard that I can go off in different directions, either as an actor or in my personal life, but that I am, I think, essentially unremarkable. I’m kind of Delaware personified. That having made some 30 movies I’m probably the most famous person ever to come from there tells you all you need to know.” His home community of New Castle is technically a city, though it has fewer than 5,000 citizens. “I guess that’s why I always had the drive to move on. Had I stayed, I think it would have been a very restricted and predictable life.”

Phillippe describes his father Richard, a chemist for Dupont, as “a cerebral man but with a natural artistic ability that due to work and us [the actor has three sisters, one older and two younger] he has rather ignored.” His mother, Susan, used the family home as the base for a day centre for children aged from two up to 11. “I’d get up for school and already there’d be ten or more kids around that weren’t part of my family”. Did he resent that intrusion on his space? “God, no. I love kids. I loved it that even though I wasn’t very old myself, I was helping younger ones to learn. And I think it also served me well when I became a young father. So much was second nature.”

When he tells me he is going back to visit his parents in a few days’ time, I remark that they must be proud of all he has achieved. “I think sometimes they feel it’s removed me from their lives,” he replies. “My kids and my work are here [in Los Angeles]. And the life I live now is so different from theirs and from the way I grew up that it can be hard for us to relate. They’re incredibly proud but feel also something has been lost along the way, and there’s a truth to that.”

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