Cool has a history. My new book on the beginnings of this key American word and concept will be published on May 22 by the University of Chicago Press. The Amazon page is now up with a great cover evoking film noir and the existential crossroads of 1945 -- after all, that's why Americans needed to be cool during the Cold War. Cool did not correspond to superficial popularity or being in vogue until the '80s. In the beginning, Cool was an underground password for searchers, a public mode of covert rebellion.