This kind of stuff makes me think of the old Adorno quotation: "To be pleased means to say yes"
I think that the excessive irony and detachment in art & culture is a product of the lack of any political sway the citizenry has in the west. There's no sense of meaningful attachment to any large political project, no investment in any kind of vision of the future, so why should art reflect/portray it? And this is probably why a lot of self-consciously "political" art seems so silly, because it really IS pointless: the cynical naysayers are usually RIGHT in this case. The American ruling class does not give a shit about die-ins, protests, letters to Congressmen, performance art, conceptual installations, any of it. Even antiwar art I like (who did those grotesque bulging Abu Ghraib comic-style pieces?) reaches few people and essentially changes nothing, and no one even pretends it will. And how could it? There's nothing at stake with most art, no one's going to get in real trouble, no one's going to prison over a painting, so say/draw/create whatever you like, and maybe you'll cause a stir to a portion of NYT readers, but that's about it. Everyone's over dada, we get it on Adult Swim now. Rappers are still considered more dangerous than most artists, and still face police harassment for songs that do nothing more than get white teenagers to dance provocatively.
So in this sense irony is like a defense mechanism, a stilted laugh to expel the pain and ennui of life as a cog in a pointless consumerist machine. It's also a wonderful way for the capitalist avant-garde to expand into new terrains of obscenity. "Wetback" jokes might have been off-limits during the "PC" '90s, but when delivered by a "Hispanic" comic with an "ironic" tone, everyone can laugh -- Carlos Mencia, whose real name is Ned Holness, and is of German-Honduran descent.
I have noticed a lot of politically involved art in my neighborhood that seems to resist the easy cynical laugh... There are dozens of murals done by Mexican/Mexican-American artists all over walls, alleys, buildings... Lots of surrealism, use of Aztec imagery, corn, portraits of revolutionary Mexicans (from Hidalgo to Subcomandante Marcos)... It just resonates more for me, seems more relevant to everyone. I think part of it is that it's real community art, in plain view for thousands of people who pass it every day, and it's done by people who aren't necessarily professional artists. It calls up a long historical memory that many people here share (everyone knows who Ignacio Allende is), complete with a recognition of bloody sacrifice that plays such a huge role in Mexican history -- you know, coming up with their own martyrs and all.