PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, NY - SEPTEMBER 11: New York City Police Officer Danny Shea, a military vet, salutes at the North pool of the 9/11 Memorial during the tenth anniversary ceremonies of the September 11, 2001 terrorist attacks at the World Trade Center site, September 11, 2011 in New York City. New York City and the nation are commemorating the tenth anniversary of the terrorist attacks on lower Manhattan which resulted in the deaths of 2,753 people after two hijacked planes crashed into the World Trade Center. (Photo by David Handschuh-Pool/Getty Images)Photo by: Pool PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, NY - MAY 15: The South reflecting pool is viewed at the Ground Zero memorial site during the dedication ceremony of the National September 11 Memorial Museum in New York May 15, 2014 in New York City. The museum spans seven stories, mostly underground, and contains artifacts from the attack on the World Trade Center Towers on September 11, 2001 that include the 80 ft high tridents, the so-called "Ground Zero Cross," the destroyed remains of Company 21's New York Fire Department Engine as well as smaller items such as letter that fell from a hijacked plane and posters of missing loved ones projected onto the wall of the museum. The museum will open to the public on May 21. (Photo by Spencer Platt/Getty Images)Photo by: Spencer Platt PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago 394261 09: Smoke Pours From The World Trade Center After Being Hit By Two Planes September 11, 2001 In New York City. (Photo By Craig Allen/Getty Images)Photo by: Craig Allen PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago 394261 14: A fiery blasts rocks the World Trade Center after being hit by two planes September 11, 2001 in New York City. (Photo by Spencer Platt/Getty Images)Photo by: Spencer Platt PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, NY - SEPTEMBER 11: Tribute in Light illuminate the New York City sky between the Twin Towers of the World Trade Center in New York to mark the 14th anniversary of the 2001 terrorist attacks on September 11, 2015. (Photo by Bilgin Sasmaz/Anadolu Agency/Getty Images)Photo by: Anadolu Agency PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, NY - SEPTEMBER 11: Carrie Bergonia of Pennsylvania looks over the name of her fiance, firefighter Joseph Ogren at the 9/11 Memorial during ceremonies for the twelfth anniversary of the terrorist attacks on lower Manhattan at the World Trade Center site on September 11, 2013 in New York City. The nation is commemorating the anniversary of the 2001 attacks which resulted in the deaths of nearly 3,000 people after two hijacked planes crashed into the World Trade Center, one into the Pentagon in Arlington, Virginia and one crash landed in Shanksville, Pennsylvania. Following the attacks in New York, the former location of the Twin Towers has been turned into the National September 11 Memorial & Museum. (Photo by Chris Pedota-Pool/Getty Images)Photo by: Pool PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago JERSEY CITY, NJ - SEPTEMBER 11: The annual Tribute in Light is illuminated on the New York City skyline marking the 15th anniversay of the 9/11 attacks on the World Trade Center on September 11, 2016 as seen from Jersey City, NJ. (Photo by Gary Hershorn/Getty Images)Photo by: Gary Hershorn PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, NY - SEPTEMBER 8: Visitors pause at the National September 11 Memorial, September 8, 2017 in New York City. New York City is preparing to mark the 16th anniversary of the September 11th terrorist attacks that struck New York City and Washington, DC in 2001. (Photo by Drew Angerer/Getty Images)Photo by: Drew Angerer PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago November 2, 2011 - The South Pool looking at the 9/11 Memorial Museum. North and South pools occupy the footprints where each of the two World Trade Center Towers stood before being destroyed in the 2001 terrorist attack. (Photo by Andrew Holbrooke/Corbis via Getty Images)Photo by: ANDREW HOLBROOKE PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago ARLINGTON, VA - SEPTEMBER 14, 2001: (SEPTEMBER 11 RETROSPECTIVE) A military helicopter flies in front of the Pentagon September 14, 2001 in Arlington, Virginia at the impact site where a hijacked airliner crashed into the building. (Photo by Stephen J. Boitano/Getty Images)Photo by: Stephen J. Boitano PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago 394263 15: (PUERTO RICO OUT) Policemen and firemen run away from the huge dust cloud caused as the World Trade Center's Tower One collapses after terrorists crashed two hijacked planes into the twin towers, September 11, 2001 in New York City. (Photo by Jose Jimenez/Primera Hora/Getty Images)Photo by: Jose Jimenez/Primera Hora PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, UNITED STATES - SEPTEMBER 11: (FRANCE OUT) Lower Manhattan and the World Trade Center after attack by terrorist hijacked airliners, which destroyed the Twin Towers and killed more than 3000 people in New York, United States on September 11, 2001(Photo by Alan CHIN/Gamma-Rapho via Getty Images)Photo by: Alan CHIN PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK CITY - SEPTEMBER 11: New York Daily News staff photographer David Handschuh is carried from site after his leg was shattered by falling debris while he was photographing the terrorist attack on the World Trade Center on September 11, 2001 in New York City. (Photo by Todd Maisel/NY Daily News Archive via Getty Images)Photo by: New York Daily News Archive PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago WEST ORANGE, NJ - SEPTEMBER 11: The annual Tribute in Light is illuminated on the New York City skyline marking the 15th anniversay of the 9/11 attacks on the World Trade Center on September 11, 2016 as seen from West Orange, NJ. (Photo by Gary Hershorn/Getty Images)Photo by: Gary Hershorn PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago Colour photograph of New York Firefighters amid the rubble of the World Trade Centre following the 9/11 attacks. Dated 2001. (Photo by: Universal History Archive/UIG via Getty Images)Photo by: Universal History Archive PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago Colour photograph of a New York Fire-fighter amid the rubble of the World Trade Centre following the 9/11 attacks. Dated 2001. (Photo by: Universal History Archive/UIG via Getty Images)Photo by: Universal History Archive PHOTOS: Remembering the lives lost in the 9/11 attacks, 16 years ago NEW YORK, UNITED STATES - SEPTEMBER 14: (FRANCE OUT) On September 14, 2001, in New York United States, President George Bush comforts New York City Fire Dept Lt Lenard Phelan of Battalion 46, whose brother, Lt Kenneth Phelan of Battalion 32, is among the 300 members of the FDNY still unaccounted for from Tuesday's terrorist attacks on the on the World Trade Center(Photo by 8393/Gamma-Rapho via Getty Images)Photo by: 8393