“Every dog has its day” is an expression believed to have come from around 405 BC when a Greek playwright, Euripides, was mauled and killed by a pack of dogs. An analogy to this tale could be the US dollar. So, is the end nigh? That is, has the mighty greenback ‘had its day’? Historically, world reserve currencies have been typically superceded and replaced as the result of military conflicts, but will the US$ be replaced not by war but a result of economics? Whilst the US economy is still the largest in the world, its economic…