The authors are British and cover America for The Economist magazine. The book attempts to explain how and why America has become such a conservative country. Their point of view is that of moderate conservatives who like America but find some aspects of American conservatism a bit strange.
It is divided into four parts:
The first part, History, is a history of American conservatism from 1952 until 2000, showing how we went from "Eisenhower Republicanism" to George W Bush.
The second part, Anatomy, goes into more detail about the modern-day conservative movement in America.
The third part, Prophecy, looks at the future of conservatism in America: why America is likely to become more rather than less conservative, what could go wrong for the Republicans, and how the Republican party might change due to the increasing influence of young people, ethnic minorities and women.
The fourth part, Exception, looks at why America has such a different political climate from Europe, both in being more conservative and in having such a different flavour of conservatism. There is a fascinating chapter on the historical reasons why America is so right-wing.
Finally the conclusion discusses how America and Europe might get along with each other despite their differences.
If this is sort of thing you find interesting, I would also recommend George Lakoff's books.