American Public Media’s Marketplace Morning Report radio show this morning tells the condensed version of the increasingly-popular story of how New York will never, ever go back to those wicked 70s. It starts with high drama: Bloomberg talking to a lot of other rich people when all of a sudden “an army of protesters — representing lower income and immigrant groups — halted the mayor’s speech.” After some hippies bellow, the announcer continues: “The scene crystallized the sentiment in the room. Fear of a return to New York’s lost decade” — a lost decade where people yelled things and, a historian says, “Subway trains, parks, bridges, buildings are just filled with graffiti.” “It took years for New York to get back on its feet,” continues the announcer — but this recession will be different. Why? Because, the historian says, “what had gone on for the last 15 years was a strengthening of a lot of aspects of city life — what you didn’t have in the 60’s and early 1970’s.” He doesn’t say what “strengthening” has taken place — maybe he means the strengthening of a sense of entitlement among brokers, politicians, and rich dorks, or of their obliviousness to reality. One good thing about the coming cataclysm is that it will shut these people up for a short while at least.