The 20th Anniversary of September 11

Introduction: A Nation Remembers 9/11

Memorial bench outside the Pentagon

The Pentagon Memorial at dusk shortly before its dedication, September 8, 2008. Photo by Petty Officer 1st Class Brien Aho.


Twenty years ago, on September 11, 2001, terrorists crashed hijacked commercial airliners into the Twin Towers of the World Trade Center in New York, the Pentagon, and a field near Shanksville, Pennsylvania. Nearly 3,000 lost their lives in what is still the worst terrorist attack on U.S. soil.

The U.S. Army Corps of Engineers mobilized in the aftermath of the attack and, under the direction of the Federal Emergency Management Agency and New York City, helped the city respond, recover, and rebuild. At the Pentagon, active-duty Army Engineers helped stabilize the building and search for survivors and victims.

The Office of History (CEHO) has created six historical vignettes to tell the story of the Corps of Engineers’ response to the tragic events of that day. The Visual Information section at USACE Headquarters has also produced a 9/11 video, showcasing images and audio from the Office of History collections.

For all products, CEHO has relied on publications from the New York District, the Historical Office of the Secretary of Defense, and the U.S. Army Center of Military History; photos from the Defense Visual Information Distribution Service; and documents, photos, museum objects, and oral history interviews from its own collections.

Office of History's series of articles remembering the responses to the attacks of September 11, 2001


September 11, 2021. Intro to nos. 144-149.