Sentiment & Irony
It's a truism that we live in an "ironic" age. (1) It is also a truism that people who discuss irony in an intellectual/zeitgeist/state of mind fashion almost 100% have no idea what they are fucking talking about, up to and including a working definition of the term "irony" itself. (2) I prefer the definition provided by M.H Abrams in his book, The Mirror and the Lamp: Romantic Theory and the Critical Tradition:
Irony in this broadest sense entails the avoidance of sentimentality through the incorporation of multiple attitudes in a single work. (3)
The reason that is the correct definition is because it contrasts irony to sentimentality, which was the "mind set" of people who actually cared about such things before those same people became modern/ironic. It's common for people bemoaning ironic postures in art and life to bemoan the fact that irony somehow "reigns supreme" i.e. that there is too much of it and that public manifestations of ironic relationships to one's surrounding need to be reduced, but only a moron who has no understanding of how deeply powerful sentimentalism was/is and always will be, would say that there is "too much" irony in the world.
It is hard for Moderns to access the Artistic products that properly convey the development of sentimentalism as a world view since we are both divorced from that pre-modern era (many sentimentalist art products date to the 18th century) and the era prior to that- the 17th and 16th centuries. It's easier to simply describe the way sentimentalists reacted very differently to events than would someone looking at the world from an ironic perspective- artist or non-artist alike.
In the "Age of Sentiment" people shed tears- A LOT- they cried over all kinds of things that someone with an ironic point of view would either ignore or laugh off- A good example of this comes in an 'Index of Tears' that was prepared in the late Victorian period for reprint of Henry Mackenzie's Man of Feeling. Each entry on the index has a page reference for each episode, and the sum total is 45 mentions of tears in a 100 page book. (4)
All this is only to say that you can't use irony in a critical sense without engaging and acknowledging that sentimentality is so powerful today that people don't even identify as a specific state of mind, it's just everyone, everywhere- everything they like- everything they do- filled with aggressive sentimentality whether it is greeting cards, talk shows, movies or just their interaction with other people during the course of the day- sentimental attitudes dominate.
(1) This is an observation that has been made in certain circles since the mid-19th century and has been reiterated ever since. A most recent illustration of the perennial homily about our "ironic" age was in the New York Times in November, See How To Live Without Irony.
(2) The classic statement of this truism is in Reality Bites, the movie, from 1994:
[assuming the question had no answer at all]
Lelaina: Can you define "irony"?
Troy Dyer: It's when the actual meaning is the complete opposite from the literal meaning. (MEMORABLE QUOTES FROM REALITY BITES IMDB)