AP Photo

Late on 1 May, Eastern Time, US President Barack Obama announced that al-Qaeda leader Osama bin Laden had been killed in a US Special Forces raid on a villa inside Pakistan. This operation represented the culmination of an intelligence operation that had begun four years previously when US interrogators in Guantanamo Bay learned of the existence of an individual who was bin Laden's principal courier and contact with the outside world. It took another two years before the CIA was able to identify the courier. A complex surveillance operation led them to a fortified villa in the Pakistani garrison town of Abbottabad and further months of careful observation led to the conclusion that the villa, which had no telephone or Internet connection, was occupied by Osama bin Laden himself.