In the age of Trump and Johnson (to say nothing of Putin, Xi, Duterte, Erdoğan, Bolsonaro, Assad, Sisi and so on), the question posed in the title of Joseph Nye’s book could hardly be more pertinent. Nye, a retired Harvard professor who held senior government posts under Bill Clinton, is famous for coining the term ‘soft power’, meaning the ability of a nation to achieve its ends through moral authority rather than coercion, or hard power. The expression has become a cliché, and rather a tiresome one since it does little more than indicate the method, well understood by politicians and diplomats down the ages, by which states exert influence through persuasion and prestige instead of the more costly use of force. Lord Salisbury made the point with characteristic trenchancy and cynicism. As far as British rule in India was concerned, he said, bamboozle was better than bamboo.

Nye is an idealist, favouring the notion that the USA can win friends and attract allies through its liberal culture and democratic values. Hence the importance he attaches to an ethical foreign policy. To gauge the extent to which presidents from Franklin Roosevelt to Donald Trump have pursued such