A couple of years ago, I wrote a book about the financial crisis for the American and British markets. Before publication, I was told I would need to make tweaks to cater for differing transatlantic tastes. So for the UK edition I included long passages about Northern Rock (the failed British bank). And in the American edition I replaced that with passages on Countrywide (the US mortgage giant). So far, so unsurprising. But the real fun erupted when I wrote the preface. Initially I planned to start the book by admitting that I was not a true expert on high finance: instead I crashed into this world in 2005, after a background spent in journalism-cum-social anthropology – making me a well-intentioned amateur, but without complete knowledge.

My friends in the British publishing world loved that honesty; in the UK, self-deprecation sells, particularly for “well-meaning amateurs” such as the writer Bill Bryson. But my American friends hated it. In New York, I was sternly told, absolutely nobody wants to listen to self-doubt. If you are going to write a book – let alone stand on a political platform or run a company – you must act as if you are an expert, filled with complete conviction. For the US version, the preface was removed entirely.

Happily for me, the book sold well in both markets. But in the past couple of weeks I have been pondering this issue of “conviction” again, since it is becoming newly relevant to America’s political economy.