One tends to forgive a lot when a people's history has been as fraught with difficulty as has the Irish. Although Irish nationalist invective is aimed towards the English these days, they are merely the most recent of invading forces that have swept across the Islands to the west of mainland England. According to legend, even the Celts were invaders at one time, sweeping the original inhabitants away, only to be pursued themselves by the Romans, who in turn were raided by Saxons and Vikings alike before the English even got it together to invade. Even the supposed hero of Ireland, St. Patrick, was an invader, as he was a second-generation Roman, born in Britain, who led an army into Ireland to purge the traditional religion and ensure the ascendancy of Christianity.
So it's easy to understand and forgive them if they tend to get maudlin and sing songs that celebrate their occasional victories over an enemy, or get sentimental over the sound of a clear tenor voice singing of the glories of a dark-haired woman's sparkling eyes. Of course, there's a world of difference between the Chieftans or The Clancy Brothers singing the old songs and The Pogues tearing a hole through tradition and singing about Irish life in the twentieth century, but it's all from the same tradition. So to make generalizations about Irish music is as dangerous as it is to make generalizations about anyone's culture.
On the other hand, it gets a little difficult not to when, in recent years, we've seen an upsurge in the promotion of big-market Celtic extravagances like Riverdance and its offshoots. One of the more lucrative successors of the dance shows has been Celtic Woman, by the musical director of Riverdance, David Downes. Currently featuring four vocalists (there have been as many as five) and a violinist backed by traditional Irish instruments, a choir, and an orchestra, the show is a mixture of Irish songs, show tunes, contemporary music, and original material in one glitzy package.
Since its inception in 2005, the production has sold millions of CDs and DVDs, yielded television specials and appearances as well as countless live performances, and its debut album hit Number One on the Billboard world music charts for sixty-eight weeks.