These are the bare facts. Following the terrorist attacks on the World Trade Centre and the Pentagon on September 11, 2001, it did not take long to establish that responsibility for the onslaught lay with the al-Qaeda movement. The US was convinced that its master-mind, Osama bin Laden, was being sheltered by the extremist Islamist group controlling Afghanistan, the Taliban. As a result, within a few weeks a US-led coalition invaded Afghanistan. The conflict has lasted ever since. In the past 19 years it has claimed the lives of more than 4,000 American military and civilian personnel. Currently about 12,000 US troops are stationed in the country.