Where have all the Irish women in Hollywood gone?

The "starlet" is the reigning female Hollywood persona. A few women have been able to evade the stereotype of the anorexic, tanorexic, baby-making, fashionista actress - I'm thinking Kate Winslet, Meryl Streep, etc. - but these women are few and far between. Unfortunately, the Lindsay Lohans of the world are the most recognizable female figures on the Hollywood scene.
So what is it about Irish actresses that doesn't allow them to cut it in the American movie scene? Are they not skinny enough, tan enough, sexual enough?

Did Maureen O'Hara work because she fit into the stereotypical "fiery redhead" Irish woman character? And since the days of Irish 'begorrah' movies are for the most part gone, are there no roles for Irish women?

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Nster.com