The query "how did 9" likely refers to the question "How did 9/11 happen?" or "How did the 9/11 attacks occur?" The September 11 attacks, known as 9/11, happened on September 11, 2001, when suicide attackers hijacked four US passenger jets. The hijackers crashed two planes into the Twin Towers of the World Trade Center in New York City, causing the towers to collapse. A third plane hit the Pentagon near Washington DC, and the fourth crashed in Pennsylvania after passengers intervened. The attacks killed 2,977 people and were carried out by the Islamist extremist group al-Qaeda, led by Osama Bin Laden. These attacks had a profound global impact and led to the US invasion of Afghanistan to dismantle al-Qaeda.

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