Martin Filler's essay in the NYRB is excellent in its totality, but these paragraphs stand out in particular:
In fact, what Lichtenstein and his five-years-younger contemporary Warhol had most in common was being the foremost exemplars of Cool among their generation of American visual artists. The first half of the 1960s was the apogee of what might be termed the Age of Cool—as defined by that quality of being simultaneously with-it and disengaged, in control but nonchalant, knowing but ironically self-aware, and above all inscrutably undemonstrative.
Coolness (which was largely but not exclusively a male attribute) suffused American culture back then, from our supremely compartmentalized commander in chief, John Kennedy, to the action-movie star Steve McQueen, nicknamed “The King of Cool,” and from the middle-class cool of the TV talk-show host Johnny Carson to the far-out jazz trumpeter Miles Davis, whose LP album Birth of the Cool could serve as the soundtrack for that brief interlude before things suddenly turned hot toward the end of the Sixties. Coolness even had its own philosopher-theoretician, Marshall McLuhan, whose influential treatise Understanding Media (1964) codified comic books and television as “cool” means of communication.(Image: Andy Warhol: Vote McGovern, 42 x 42 inches, 1972)