9/11: Remembering America's tragedy 20 years after Today marks the 20th year anniversary of the tragedy where nearly 3,000 people lost their lives, across the US, UK and the world. The September 11 attacks, referred to as 9/11, was a series of four coordinated terrorist attacks by the militant Islamist terrorist group al-Qaeda against the United States of America, on Tuesday, September 11, 2001. On that morning, four commercial airliners traveling from the northeastern United States to California were hijacked mid-flight by 19 al-Qaeda terrorists. The hijackers were organised into three groups...