As leaders from around the world gather at the United Nations this week for a global summit on climate change, the outlook is gloomy. The U.S, historically the world's worst polluter, can't even decide if man-made climate change exists. Meanwhile, China, the current king of greenhouse gas emissions, is reluctant to sign on to any climate change pact that would hinder its growth. All of which got me thinking about Sting.

Butterfield’s almost wistful point is clearly rhetorical - but it raises important questions about the way we organize our thoughts on diplomacy, the flows and breaks in its development - even how diplomacy is conducted by constantly evolving states.

At the height of the Cold War, the US State Department deployed a new weapon in its fight against communism – jazz. Over a period of 20 years, it dispatched some of the greatest musicians – Dizzie Gillespie, Louis Armstrong, Duke Ellington –to play in Africa, Asia, the Middle East and even the Soviet Union, where Benny Goodman tooted his clarinet in Red Square, in a battle for hearts and minds. The New York Times of 6 November  1955 reported on its front page: “America's secret weapon is a blue note in a minor key.” Louis Armstrong was named as “its most effective ambassador”.