On Tuesday lunchtime it was confirmed that Heathrow airport will be getting a third runway. It has been one of the most hotly-debated transport topics in recent years and, not surprisingly, politicians have been hugely divided over it. It will cost £17.6 billion, lead to 783 homes being demolished, and will inevitably contribute to climate change. BUT it will provide an enormous boost to the economy. So who exactly thinks what?The Foreign Secretary has previously said that he was prepared to "lie down in front of bulldozers" to stop the proposed expansion of the world's busiest airport. When the government gave the third runway the green light this afternoon, Johnson reacted by saying:"No other great city would do this to its inhabitants. New York is going to be the city of beautiful skyscrapers, Paris the city of lights and London in the future, if we go ahead with this project, will be known as the city of planes."