The Economist explains

TO TRIUMPHANT shouts of “banzai!” it was announced on September 7th that Tokyo would host the 2020 Olympic games. The city fended off not-especially-stiff competition from Madrid, whose chances were damaged by Spain’s sickly economy, and Istanbul, whose image was tarnished when its police spent the summer practising for the 100-metre baton-charge. It was not the strongest field of candidate cities in Olympic history. But the contest demonstrated the lengths that countries will go to for the privilege of hosting the world’s biggest sporting bash. Shinzo Abe (pictured above, third from right), Mariano Rajoy and Recep Tayyip Erdogan all flew to Buenos Aires, where the International Olympic Committee (IOC) was voting, to make the official case for their respective countries. Tokyo had previously bid unsuccessfully for the 2016 games; Madrid had bid for both 2016 and 2012. Poor Istanbul has now been rejected five times. Why are cities so keen to host the Olympics? :http://www.economist.com/blogs/economist-explains/2013/09/economist-explains-0#!

Genel