America is observing the 25th anniversary of the September 11, 2001, attacks. The day, which profoundly altered the United States, is being commemorated with reflections on its impact and enduring hope.
In a special look back, ABC's David Muir revisits the events of 9/11. The anniversary coverage includes a focus on a phone call made decades later, symbolizing the passage of time and the resilience of the human spirit.