An era can be said to end when its basic illusions are exhausted.

Arthur Miller (1915–2005) American playwright and essayist

Essay (1974-12), “The Year It Came Apart,” New York Magazine, Vol. 8, No. 1
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The year discussed in the essay is 1949 (the theme of the issue), which Miller describes as the last year of the Postwar Era, marking the end of the hopeful, unified times following World War 2.