The success of a book can sometimes tell you as much about the times as about the book itself. That may be the case with Why Nations Fail, which was published last year to great acclaim from reviewers and prize juries, and even compared to Adam Smith’s Wealth of Nations.

The book, by Professors Daron Acemoglu and James Robinson, is certainly erudite and interesting. But the excited reception for Why Nations Fail may also have something to do with the fact that its message is deeply reassuring to many in the west. I finished the book this weekend, surrounded by newspapers predicting that the US will, this week, slash its budget so deeply that it puts hundreds of thousands of jobs at risk. Meanwhile, the Italian elections threaten to reignite the eurozone crisis.

But do not despair. Hurl the newspapers to one side – and take the long view. Based on a magpie-like assembly of evidence from many centuries, the authors of Why Nations Fail have concluded that, for all its difficulties, western-style democracy is the key to long-term prosperity. The professors argue that countries “such as Great Britain and the United States became rich because their citizens overthrew the elites who controlled power and created a society where political rights were much more broadly distributed”. Professor Ian Morris, a reviewer, summarises their argument, thus: “It is freedom that makes the world rich.”