It is now more than three years since the 9/11 attacks. But the collapsing towers, the smoldering Pentagon, the round bland face of Mohammed Atta still have an intense immediacy. Most people will always remember where they were when the news came through. If some of the details have faded, the mantra "the world has changed" seems as relevant as ever. The attacks on the World Trade Center and the Pentagon on 11 September 2001 had an immense impact on global history. A retaliatory strike against the Taliban has mutated into an open-ended campaign to transform the Middle East. An unpopular president with a doubtful mandate has been able to make far-reaching changes to the US constitution and oversee a massive transfer of wealth to the rich. None of this would have been possible without the 9/11 attacks, yet the events of the day and the period directly prior to the attacks are filled with unanswered questions. Rowland Morganis independent journalist and author who was a weekly columnist for the Independent on Sunday and the Guardian in the 1990s is now asking these questions. Back-up photos are included.