WHO is the most famous Scot ever?

Not the Scot who has had the most impact on our lives - that's for Fleming, Logie Baird. Bell and Watt to fight over. No, who is the Scot most known around the world. Robert Burns? Certainly among those who read books and poetry, he has his place. But which Scot had two million people on the streets of New York city yesterday proclaiming his name?

Yes, St Patrick. Wait, isn't he Irish? Not a bit of it. St Patrick was born near Dumbarton. He unfortunately strayed too near the shoreline and was picked up by pirates who took him to Ireland. It's a moot point whether years in slavery in Ireland is worse than living in Dumbarton, but we digress.

Yes St Patrick, whose name, coupled with the sophisticated marketing of the Guinness brewing empire, has led to a day of alcohol-fuelled celebration the world over which is unmatched by any other country.

But even that proud boast is tinged with sadness. As Paddy Callaghan, organiser of the Glasgow St Patrick's Festival points out, it was only the fact that Ireland exported its starving millions around the world after the potato famine, that so many countries heard about St Patrick. If Ireland could have supported its own children, St Patrick's Day would have remained an Ireland-only celebration.

It was Irish militia in New York in 1762 who marched two blocks to a tavern on St Patrick's Day who started the annual celebrations in that city that today sees 200,000 people taking part in the floats and bands, watched by 10 times that figure on the pavements.

It is, of course, a weird bastardised version of Ireland. Some will be dressed as green-wearing leprechauns. I once wrote an article decrying a bookies that had midgets dressed as leprechauns to publicise the Cheltenham Festival. Days later I received a polite letter from one of the dimunitive actors saying how dare I decry one of his biggest-earning pay days.

Americans love St Paddy's Day as it gives them a link to their past. A reader was in Dublin on St Patrick's Day when a local, realising he had spent his money, went outside the pub, saw a plastic bucket, turned it upside down, and played a drum paradiddle on it with bits of stick. A delighted American couple, believing they were witnessing real Irish culture, threw a few euros. He picked up the money, discarded the sticks, and went back inside to buy another pint.

In Glasgow yesterday, St Patrick's Day began with a breakfast at the Indigo Hotel, where manager Denis McCann annually marks St Patrick's Day with a celebration for the Irish business community in Glasgow. Not that they were always welcome. One Irishman told me that when he arrived in Glasgow he found many Glasgow golf clubs didn't want a Catholic as a member. Instead, he was invited by a Jewish customer to join Bonnyton outside Newton Mearns, set up by Jewish golfers, who were happy to accept another outsider.

Nowadays most Scottish golf clubs are begging for members, so your religious affiliation is not questioned as long as you can cover the membership fees. Progress, some will call it, economic necessity, others will argue.

Perhaps it's because they had no empire to lose, and don't regard themselves as major players on the world stage, but Denis says that the Irish don't take themselves too seriously. They laugh at themselves and have a natural optimism no matter what they have to face.

Not everyone has such joie de vivre. An American once told me that he was visiting Stratford-upon-Avon where he asked what St George's Day was all about. "It's like St Patrick's Day," a local replied. "But without all the fuss."

Denis himself argues that Ireland was the first country to set up a "global social network". "Or as other countries call it," says Denis, "emigration."

"The luck of the Irish" will be muttered often. But it is hard to see the luck of a country which has faced famine, economic ruin, and the flight of its youngsters seeking work abroad.

In Glasgow, the St Patrick's Festival, which ran for the past fortnight, is an attempt to highlight the cultural aspect of St Paddy's Day rather than simply an excuse to drink far more alcohol than is wise. It has been running for seven years, with a very limited budget, with plays, musical nights, and a family day at the weekend. Such are the scars of sectarianism, that in Glasgow some people view a St Patrick's Festival with suspicion, believing it to be a celebration of only one half of the religious divide. But in truth, the religious aspect of St Patrick's Day is dwindling. Few even in Dublin yesterday attended a Mass to celebrate their patron saint.

In Belfast, the St Patrick's Day Parade is growing in popularity. Instead of violence, Ireland is becoming better known around the world for its rich culture of music, poetry and writing.

I was in Dublin once where I asked a local if it was true that St Patrick drove the snakes out of Ireland - not quite true as the chilly waters around Ireland has meant snakes never arrived there in the first place. "It's a metaphor," he told me, "for the Catholics driving the Protestants out of Ireland."

Seeing my shocked face, he quickly added: "I'm joking - here let me buy you a pint." It's true, alcohol can cure many a slight.

As Denis McCann at the Indigo Hotel told me: "No matter what has happened in Ireland, the Irish have a natural optimism, that tomorrow will be better than the day before."

And who could argue with that as a signpost to your future.