Today being St. Patrick's Day, I was thinking of the ironic term, "The Luck of the Irish." Historically, to be Irish is certainly not very lucky. I suppose if it weren't for bad luck the Irish would have no luck at all. Just like Irish humor tends to be wry, ironic and a wee bit dark, the phrase is actually meant to point out one's unlucky experiences and its earliest roots can be traced back to Ireland before any immigration to the United States. In coming to the US, the Irish have withstood not a small amount of racism over the years and when Americans used the phrase it was because they couldn't believe the Irish were actually smart enough to succeed on their own merits, such as when they frequently struck gold in the American West, so it must be luck. So while the Irish use the term ironically, Americans tend to use it literally. It's like an inside joke, and now you get it.
For some perspective, Cracked.com has a great piece on this called "6 Reasons the Irish Aren't So Lucky."
Luck in the tarot is Fortuna, better known as The Wheel of Fortune, and just like the Luck of the Irish, it isn't always good luck that is portrayed. The name Fortuna may have its root in the Latin fero, meaning "to bring, win, receive, or get" or Fortuna's name may derive from the Etruscan Goddess Voltumna, whose name encompasses ideas of turning and the alternating seasons.
In reading for clients I often stress less fate and more direct control over the circumstances in one's life. However, I cannot deny the reason most people want a tarot reading is to gain a bit of an edge over Fortuna, to glimpse into her plans, if she even has any. I am not convinced she does. While some are happier with the notion that "everything happens for a reason" I really don't believe that. I think we make reason and sense of things in hindsight, after the fact, because we have a need to believe there is an orderly parade to Fate's decisions. I think Fate can conspire with other forces, most of which lie within ourselves, to bring about good fortune. We often say, "But if that [insert Bad Luck Thing] didn't happen, I wouldn't be who I am today." True enough, but I am not certain that it was Fortuna's plan to assist your growth. It all depends how you use the Bad Luck Thing in your life. We can, like the Irish, persevere and overcome with strength and humor, or we can let it beat us under the crushing weight of the Wheel. Therein I believe is the true "Luck of the Irish." It is the ability to turn our fates to good no matter what Bad Thing may happen.