Donald Trump and Hillary Clinton are seen as the most unpopular candidates to have ever stood for the presidency of the United States. So why is it so difficult for a third party candidate to break through and make a real impact? Owen Bennett Jones and his guests discuss whether the US political system, trumpeted as a shining beacon of democracy across the world, really does give the voter the best choice. (Photo: A Trump supporter at the first US presidential debate in September 2016. Credit: Getty Images)