The former I can forgive, for in a trade fuelled by malice and spite, who amongst us does not die a little inside when someone we know does well? (But those critics do need to change the record. For the ignorant still bought into the plagiarism slander, McWilliams is using demographic profiling common to marketers for 30 years and used by others, most recently in Microtrends: The Small Forces Behind Tomorrow's Big Changes, by Mark Penn, CEO of PR giant Burson-Marsteller and Hilary Clinton's adviser. ) But the latter . . . who pretend to believe that McWilliams is some idiot doom merchant willing the Irish economy to implode . . . are just embarrassing themselves with the magnitude of their error.

McWilliams' problem is not that he's an irrational pessimist. It's that he's irrationally exuberant about Ireland's future potential.

Specifically, to secure a new, prosperous Hibernia for this century, McWilliams calls for an Israeli-inspired "right of return", a proposal to turn Mary Robinson's Diaspora sentiment into an immigration policy. Having communed with the far-flung reaches of Greater Ireland . . . from the rejected repatriate Geoghegan sisters of Buenos Aires, to Wayne Rooney's Scotty Road Liverpool nan, to supremely tanned snowbird CEO Jack Welch . . . McWilliams senses a hunger for identity amongst this Global (Lost) Tribe. With 70-odd-million of them scattered around the richer parts of the world, Ireland is the Saudi Arabia of social networks.

In The Generation Game, McWilliams proffers a bargain to wayward Irish-Americans, told from boyhood that they are Irish, sent to the University of Notre Dame and aching for authenticity: "We can save their soul and they can build our economy."

Ireland welcomed tens of thousands of Yanks already . . .

though most of them would have more affinity with the brand of their multinational finance, tech or pharmaceutical corporate employer than with brand Ireland. Most rotate through, leaving no more trace than a carbon footprint and a legacy of better coffee and bagels.

Some of us came for the drink and stayed for the company, even when the knowledge that you're not going 'home' to the US leads some to drop the failte pretence.

The fundamental and irreducible question is whether the society we've been invited to join is prepared to accept us as full members. As the saying goes, you import workers and you get people.

Indeed, there are Laverys and Barringtons who, with the effortlessness of aristos, can float back into acceptance. But for others, integration isn't so simple. Take the descendant of John Cullen, a Blackrock College boy from Stillorgan who got himself a gig digging New York's Subway tunnels by turning up, grabbing a pickaxe and refusing to leave on payday . . .

that week and for the next 30 years . . . until he held the wages for a job he was never offered.

Cullen's grandson weds in the same church that baptised de Valera, St Agnes on E43rd Street. His son has said emerald-tinted boyhood complete with cupla focail, four years of student section cheering the Fighting Irish and fumbling awkwardly with the girls of St Mary's College, some tentative strolls through the celtic twilight. A century after his Cullen ancestor left, our nonIrish-passport test case returns to celtic tiger Dublin.

Basically, McWilliams wants Ireland to import more off me. Well, actually he'd prefer better, brighter, more productive versions of me, and I have doubts as to how many of me the Irish market will bear. But it's a problem, because . . . as in Israel . . . the descendants of returnees and of those who stayed don't always make a "perfect fusion".

The reason there are few optimists in Europe is that most of them moved to the US. Ireland imposes an import tariff on hope. Some of us Global Tribesmen are willing to pay. But probably not as many as McWilliams hopes.