A picture taken 20 May 1986 in New York shows the Statue of Liberty and the Twin Towers of the World Trade Center in the background. The Twin Towers collapsed 11 September 2001 after being damaged by two hijacked planes. (Credit: Mario Suriani/AFP/Getty Images)
Satellite Images of Terrorist Attack Sites
A satellite image of lower Manhattan shows smoke and ash rising from the site of the World Trade Center at 11:43 a.m. September 12, 2001 in New York City. (Credit: spaceimaging.com/Getty Images)
World Trade Center Attacked
A fiery blasts rocks the World Trade Center after being hit by two planes September 11, 2001 in New York City. (Credit: Spencer Platt/Getty Images)
Two Planes Crash into World Trade Center
Smoke pours from the World Trade Center after being hit by two planes September 11, 2001 in New York City. (Credit: Fabina Sbina/Hugh Zareasky/Getty Images)
Smoke billows up from the ground after one of the
Smoke billows up from the ground after one of the towers of the twin towers of the World Trade Center towers collapsed 11 September, 2001 in New York. (Credit: Henny Ray Abrams/AFP/Getty Images)
World Trade Center Attacked
Smoke pours from the World Trade Center after it was hit by two planes September 11, 2001 in New York City. (Credit: Robert Giroux/Getty Images)
World Trade Center Attack
People walk in the street in the area where the World Trade Center buildings collapsed September 11, 2001 after two airplanes slammed into the twin towers in a suspected terrorist attack. (Credit: Mario Tama/Getty Images)
A firefighter walks through rubble of the twin tow
A firefighter walks through rubble of the twin towers of the World Trade Center as a US flag hangs from a traffic light post 11 September, 2001, in New York. Two planes controlled by hijackers crashed into the buildings, destroying both. (Credit: Doug Kanter/AFP/Getty Images)
Firemen walk amid the smouldering rubble of the Wo
Firemen walk amid the smouldering rubble of the World Trade Center following a terrorist attack 11 September 2001 in New York. A hijacked plane crashed into and destroyed the landmark structure. (Credit: Alex Fuchs/AFP/Getty Images)
The rubble of the World Trade Center
The rubble of the World Trade Center smoulders following a terrorist attack 11 September 2001 in New York. A hijacked plane crashed into and destroyed the landmark structure. The all-out war on terrorism unleashed by Washington after the attacks marked a turning point in US-Arab relations and nowhere more so than in once top ally Saudi Arabia. With 15 of the 19 suicide hijackers carrying Saudi nationality and mastermind Osama bin Laden being the scion of a leading Saudi family, the desert kingdom and world oil kingpin, suddenly found itself on the frontline of the war on terror prosecuted by US President George W. Bush. (Credit: Alex Fuchs/AFP/Getty Images)
First Steel Beam Raised As Construction Of New Yorks Freedom Tower Begins
A commemorative steel beam is raised at the site of the Freedom Tower at Ground Zero December 19, 2006 in New York City. Several 25-ton steel beams were erected with fanfare at Ground Zero, marking the first vertical construction of the planned 1,776 foot tower at the site of the Twin Towers. (Credit: Chris Hondros/Getty Images)
Construction Continues On One World Trade Center
Construction continues on One World Trade Center in New York. (Credit: Getty Images)
Final Section Of One World Trade Center's Spire Installed
A couple looks on as construction continues on One World Trade Center in New York. (Credit: Getty Images)
Construction Continues On One World Trade Center
Construction continues on One World Trade Center in New York. (Credit: Getty Images)
Final Section Of One World Trade Center's Spire Installed
The new skyline in New York City. (Credit: Getty Images)