Nearly 25 years after the deadliest terrorist attack in U.S. history, Americans are preparing to mark another Sept. 11 anniversary and remember the 2,977 people killed when four hijacked planes struck ...

Part 1 of ABC News' five-part series on the 20th anniversary of 9/11 looks at the ongoing questions of how the attacks could ...

Since then, US military and influence operations have largely failed to achieve their stated goals of spreading democracy and making the world a safer place.

The annual 9/11 ceremony is adding a seventh moment of silence. Here's who it honors and why it matters 25 years later.

Today is the 25th anniversary of the Sept. 11 terror attacks. One of the many unfortunate consequences of that day is that Islamophobia persists through Western ...

The FDNY released a landmark report on the September 11th terror attacks and the impact on first responders' health in the 25 years that have followed. The report ...

Muslim Americans pointed to rhetoric, policies and attacks that they say make the current landscape even more contentious than it was in 2001.

Twenty-five years after the September 11, 2001 terrorist attacks, new research is examining the lasting health effects of 9/11 on World Trade Center first responders including evidence of accelerated ...

Tunnel to Towers' 343 Homes Initiative honors Stephen Siller and the 9/11 firefighters with mortgage-free homes for fallen ...

Brent Hoffman was doing what millions of Americans were doing on the morning of Sept. 11, 2001. He was watching television, trying to understand why a plane had crashed into a ...

New York is remembering 9/11 in numerous ways throughout the day Thursday, with somber events that also reflect the resilience of the city, marking the final hours ...