Postmodernism is a fancy word — in terms of culture, nihilist; in terms of politics, an equality of result and the ends justifying the means — that a lot of people throw around to describe the present world of presumed wisdom that evolved in the last part of the 20th century.
“After modernism” or “beyond modernism” can mean almost anything — nihilistic art that goes well beyond modern art (think a crucifix in urine rather than the splashes of modernist Jackson Pollock). Or think of the current English Department doggerel that is declared “poetry” (no transcendent references, echoes of classicism, no cadence, rhyme, meter, particular poetic language, theme, structure, etc.) versus Eliot’s or Pound’s non-traditional modern poetry of the 1920s and 1930. In politics, there is something of the absurd. The modern age saw life and death civil rights marches and the commemoration of resistance to venomous racial oppression; the postmodern civil rights marches are staged events at the DC tea party rally, as elites troll in search of a slur, or Prof. Gates’s offer to donate his “cuffs” to the Smithsonian as proof of his racial “ordeal.”
Genres, rules, and protocols in art, music, or in much of anything vanish as the unnecessary obstructions they are deemed to be — constructed by those with privilege to perpetuate their own entrenched received authority and power. The courage, sacrifice, and suffering of past American generations that account for our present bounty are simply constructs, significant only to the degree that we use the past to deconstruct the race, class, and gender power machinations that pervade contemporary American exploitive society. History is melodrama, a morality tale, not tragedy.