Final answer:
The event being described is the 9/11 terrorist attacks, which saw the loss of more than 3,000 American lives, the destruction of the World Trade Center, and damage to the Pentagon.
Step-by-step explanation:
The event being described is the 9/11 terrorist attacks. On the morning of September 11, 2001, nineteen terrorists hijacked four commercial airliners, crashing two into the World Trade Center towers in New York City, one into the Pentagon in Washington, DC, and the fourth into a field in Pennsylvania, thanks to the heroic actions of passengers aboard Flight 93. These attacks resulted in the loss of more than 3,000 American lives, the destruction of the World Trade Center, and damage to the Pentagon.