Mayor Michael Bloomberg's Irish jokes gaffe earned him 'Knucklehead of the Week' award from The New York Daily News yesterday, but the reality is that he will not be the first or last politician to tell a bad Irish joke.

Indeed, Bloomberg has often used another Irish joke in his routine, which he has used often in Ireland as well as America.

This one involves an Irish guy who is dared to drink ten pints of Guinness in a row. He disappears for a while and when he comes back he says he has been across the road in a different Irish bar, trying out to see if he could do it.

Okay, not very funny.

Senator John McCain is another politician who has a single transferable Irish joke that he tells on many occasions to Irish audiences.

It involves the O'Reilly twins, drinking in the same bar, pretending they don't know they are twins and discovering they are from the same town, same street etc.

It is part of the repertoire of many American politicians.

Senator Chuck Schumer of New York uses a different tack, always referring endlessly to the Irish relatives who married into his family.

Former Senator Al D'Amato pretty much did the same thing when he was in active politics.

It can be cringe-inducing stuff

Ronald Reagan always had a version of an Irish joke ready for any and all occasions, as did House Speaker 'Tip' O'Neill.

Most people considered them pretty harmless as do I.

It is all part of the social cohesion where so many Americans from different ethnic backgrounds meet and greet each other.

Most use it to break the ice, to connect with an audience by getting a laugh.

But how do you know when a joke crosses that line from cute to contentious?

Answer is you don't. Its a bit like pornography, you know it when you hear it.

Where Bloomberg made his mistake was referring to a real institution, the American Irish Historical Society (AIHS) and implying that a bunch of drunks ran the place.

It was a bit like saying the Metropolitan Museum is run by alcoholics.

As The New York Times made clear in a Saturday article, nothing could be further from the truth about the AIHS.

The AIHS is housed in the greatest Irish building in America, a Fifth Avenue townhouse and features cultural, artistic and scholarly pursuits which makes its members the very last people to pin such a description on.

So Bloomberg might have been better sticking to his fictional joke.

So when you add up the Bloomberg gaffe, a press eager to highlight problems in his controversial third term and an Irish controversy made for tabloid headlines such a 'Irish Stew' it is clear why the story caught on.

As for the mayor one can imagine he'll check more closely on what to say before his next Irish audience.

As will many other pols.