'To Foley. Good Job. Best wishes, George W Bush." The signed photo of Dubya was sitting there on the side-table in the drawing room of the American ambassador's residence one minute and the next it was gone, whisked away by hands unseen after I'd shown a – perhaps impertinent – interest in the inscription, taking an opportunity to snoop at the art and framed photos while Ambassador Tom Foley was having his photo taken.

The art is spectacular. Thanks to the art in embassies programme – which allows ambassadors to select from an extensive collection the pieces that they would like to hang during their posting – it includes a Hopper and a Sol LeWitt wall painting executed in situ, and Foley has brought several pieces from his own collection including a Matisse and a Leger.

Tom Foley is a lean, handsome man of 57 with a good head of hair and fine American teeth, in a navy suit with the nipped-in waist that men of a certain age who manage to stay in shape tend to favour, the trousers held up with one of those fancy Kieselstein cowboy-style belts with the real silver buckles that says 'I may have to wear a suit for work but underneath it all I'm a macho guy who'd be happier out on the ranch doing some real work'. I get the impression that he cares about how he's going to look in these photos.

A Chicago native, Foley is fourth-generation Irish American. He had been to the west as a tourist a couple of times before being appointed, but had never visited Dublin. "Growing up," he tells me, "we didn't consider ourselves as ethnically Irish; we did not connect with our Irish roots, or have any understanding of our culture and DNA."

Foley has the patrician bearing of an Episcopalian Wasp, rather than an Irish Catholic, and I'm guessing that his family – business people all – perhaps chose to distance themselves from the peasant roots that they might have considered déclassé. He was educated at Andover (where Foley's 18-year-old son, another Tom, is currently a senior) and Harvard, as was George W – a friend of Tom's older brother.

He is a long-time friend of the Bush family and was a Bush-Cheney campaign supporter whose loyalty was rewarded with the Dublin posting, one of several ambassadorships that is political rather than made from the ranks of the career foreign service and is therefore in the direct gift of the president, to whom he reports (as well as to the secretary of state through the State Department.) "The big advantage of the system, which can be controversial," he says, "is that I have a direct line to the president. He's a personal friend."

I wonder how often he does that, without really expecting him to tell me. "I've done it a few times, for example around the time of the bilateral meeting on St Patrick's Day, to discuss the agenda and make sure that everyone who should be there is invited to the White House."

A multi-millionaire 'corporate turnaround specialist' with business interests in the aviation services and textile industries, Foley spent seven months in Iraq between 2003 and 2004 living in a four-man trailer, working as an economic lieutenant on the reconstruction of Iraq. He speaks now of the work having been interesting and challenging ? "it was an honour to serve my country," he says, in the manner of a military man, which he is not and never has been ? but at the time he said controversially that the opportunities afforded by Iraq were the modern equivalent of the California gold rush of the 1850s.

Foley has retained his business interests during his Dublin tenure, whilst abiding by the rules that preclude him from sitting on boards or serving as an officer of any corporation. He holds the majority stake in any company in which he invests and so has good management teams in place to run them, guys who'll return his calls. He tends not to play the stockmarket or invest in banks, and says he has been unscathed by turbulence in the financial markets. He is confidently anticipating that there will be interesting business opportunities over the next couple of years into which he is looking forward to getting his teeth stuck when he returns home this week. As well as getting back to business, Foley will be putting time into a charity that is seeking to improve standards in the public schools in the inner cities of Connecticut. He regards home as Greenwich, CT, the hedge-fund capital of America, and effectively a suburb of New York.

So has the departing American ambassador done a good job in Ireland? The impression is that Foley hasn't had a whole lot to do – there has been little controversy during his two-year tenure and no Northern tensions to occupy his time as they did some of his predecessors'. His boss never made it to Dublin, and so the younger Bush's name is not written in gold lettering on the wooden panel in the entrance hall of the house alongside those of JFK, Clinton (three times) and the other presidents who have made the journey to the auld sod. President Bush did stop off in Belfast in June 2008 on his European farewell tour and Foley is understandably disappointed that his schedule did not allow for a diversion to Dublin.

Has it been difficult being the personal representative in Ireland of a very unpopular president? "I think the worst of all that was over when I arrived in Ireland. I take the view that George Bush is misunderstood and will be judged more sympathetically by history. I don't see my role as being one of attempting to change people's opinions about the president, but rather to open their minds to a different way of thinking."

A trawl through the online archives throws up plenty of speeches and openings, a symposium on philanthropy here, a conference on inward investment there. He claims to have found none of it tedious, because he gets to choose which gigs to accept and opts for anything to do with children or the arts.

When engagements are distant, he likes to helm the plane that takes him between them ? "and we tend not to take the direct route from A to B. I discovered a while back that what I like most in the world – well, perhaps not most but pretty much – is moving through three-dimensional space – flying, skiing and riding big motorbikes."

There have been plenty of dinners and parties. Foley has made something of a name for himself as a man who throws a good bash and he seems pleased when I tell him this, acknowledging that the beautiful house and the opportunities for hosting are one of the perks of the job. The party he threw in the Guinness Storehouse on election night is the stuff of legend. A friend who drives through the Phoenix Park and past the residence often says there are always marquees being put up and taken down, and catering vans trundling in and out of the gates. Foley has developed friendships with writer Sebastian Barry and film director Jim Sheridan, and with Louis Le Brocquy and his wife, the artist Anne Madden, but is far too discreet – he is a diplomat after all – to tell me any good stories about them. "What goes in the residence stays in the residence," he says, leaving me in little doubt that there has been plenty of fun.

Urbane, with a quick wit and an easy manner and the smarts to avoid allowing himself to be typecast as textbook neocon, despite a bunch of evidence to the contrary, Foley has, predictably, been popular with the laydees during his stay in Dublin. Gossip-column reports have linked him with writer Sarah Owens, actor and model Michelle McGrath, actor Paris Jefferson and, most often, RTé personality Mary Kennedy. As a single man in a high-profile position, he says he has been flattered by the level of interest in his love life "but surprised at how inaccurate most of the reporting has been". There had been speculation that he would be missed in certain quarters – that is until he sprung one on the guests at his farewell reception last week by announcing his engagement to Washington insider Leslie Fahrenkopf, a former associate counsel to George Bush in the White House. There's nothing like keeping it in the family.

I liked Tom Foley more than I had been expecting to – how could you not take to an ambassador who has a box of Ferrero Rocher on the coffee table and offers you one when you're leaving? ("Everyone brings them, and they all think that they're the first to have thought of it") – but can't help wishing he played for the other team. How much better would it have been to have him here for an Obama presidency?