What is the theme or summary of the book The Right Stuff?

Tom Wolfe's novel, The Right Stuff,
describes the early days of the United States space program and the men who helped
launch the first manned flights. It is a book about the men who had "the right stuff"--a
combination of heroism, bravery, talent and athleticism--who began as test pilots and
who ended up as the famed Mercury astronauts. One of the primary characters is legendary
test pilot Chuck Yeager, whose fearlessness above the clouds became the epitome of the
dangerous missions undertaken by the pilots. Although not one of the Mercury astronauts,
Yeager's daring inspired many of the other pilots who tested the supersonic crafts being
built as a response to the USSR's own burgeoning space program. Yeager lived most of his
life out of the spotlight, as compared to the first astronauts, who became media heroes
before they circled the Earth. Yeager disdained the astronauts, who he considered merely
passengers aboard the space crafts and not true
pilots.

Wolfe explores the politics that the space program
encountered, using the backgrounds of the Cold War, Cuban missile crisis, and the
Vietnam War in the process. But the novel never strays far from the characters--such as
John Glenn, Gus Grissom and Alan Shepard--who risked their lives in those first,
dangerous missions in the tiny Mercury crafts.