John Kennedy called it a long, twilight struggle. Now an extraordinary documentary traces the arc of our terrible, hopeful age

Maybe we do live in an age of miracles. Here's one: after a 40-year conflict that held the entire world in a state of terror about the possibility of nuclear annihilation, the U.S. and the former Soviet Union reconciled peacefully. And here's another: a commercial American television network has produced a 24-part series about this epoch that is serious, thorough and absorbing. CNN's Cold War, which debuts Sept. 27, serves as an example of documentary television at its best. Watching it, one begins to understand how the stamina of the U.S., the self-deception of the Soviet Union and the ultimate prudence...