See "Commemerate 9/11" article by 9/11 Memorial & Museum https://www.911memorial.org/commemorate-911-0
Here is Alice M. Greenwald, President & CEO of the National September 11 Memorial & Museum's message (https://www.911memorial.org/presidents-message):
"On September 11, 2001, nineteen terrorists hijacked four commercial airplanes and, in a coordinated attack that transformed the planes into weapons, intentionally flew two of the planes into the Twin Towers of the World Trade Center and another into the Pentagon in Arlington, Virginia. Learning of the other hijackings through telephone calls, passengers and crew on the fourth plane, now headed toward the nation’s capital, tried to breach the cockpit to thwart another horrific attack. In response, the hijacker pilot crashed the plane into a field near Shanksville, Pennsylvania. Nearly 3,000 innocent people were killed that day, the single largest loss of life resulting from a foreign attack on American soil and the greatest, single loss of rescue personnel in American history. Over 400 first responders perished while performing their sworn duty: firefighters, members of the NYPD and PAPD, and other rescue workers.
Located at the World Trade Center site – at the epicenter of Ground Zero – the National September 11 Memorial & Museum bears solemn witness to the 9/11 attacks, and to the bombing of the World Trade Center eight years earlier, on February 26, 1993, resulting in the deaths of six individuals. It is because of what happened here and in Arlington and near Shanksville, that we have an obligation to remember and to tell the story, an obligation that acknowledges the sacrifice of families and friends who lost loved ones; recognizes those who survived; honors the rescue and recovery workers whose dedication paved the way to healing and rebuilding; and responds to the millions of Americans and visitors from around the world who come to this sacred site to pay respects and learn about what happened.
Ours is a dual mission of commemoration and education: to preserve this crucial history for future generations and to be the global focal point for telling the story of what happened on 9/11 and in 1993 through first person accounts, artifacts, and digital documentation. It is through the Memorial and Museum that we honor and remember those who died in the attacks through the lives they lived, rather than the deaths they died, and stand witness to the many stories of bravery and sacrifice. Here, the number 2,983 is never an abstraction.
As an educational institution, the Museum strives to establish a level of literacy about the historical context for the events of September 11, the nature of the world in which we live, the reality of terrorism, and the often incompatible political forces that remain in tension with one another. But this Museum isn’t only about documenting history. It is about understanding our humanity. The National September 11 Memorial & Museum is a place for understanding ourselves and the world in which we live. It is a place for all of us to begin to imagine together the kind of world we want to build for the generations that will follow us."
As for me, on this 18th anniversary of the deadliest terrorist attack in world history, I hope we never forget the victims and tremendous loss, but that we also remember the acts of heroism and the unity and strength the people of the United States showed that day for each other and freedom. Go forward, be kind, take stock of what has happened, grieve our losses and deliberately make the world a better place by not repaying violence for violence.