The Songs of a Downwardly Mobile Summer

With every passing year, Miley Cyrus’s 2009 single “Party in the U.S.A.” comes to feel more like an artifact of an empire before its fall. When the Disney Channel star sang about hopping off the plane at LAX with a dream and a cardigan—on the way to turn her country-girl ambitions of fame into Hollywood reality—she projected an image of a nation that still believed in its own myths, trusted its power centers, and grooved together to the same songs. The guitars fizzed like a fresh can of Coke,…