One World Trade Center, center, rises above the National September 11 Memorial and Museum at the World Trade Center, Thursday, Sept. 6, 2012, in New York. Tuesday will mark the 11th anniversary of the terrorist attacks of Sept. 11, 2001. The World Financial Center is on the left, and Four World Trade Center is at right. (AP Photo/Mark Lennihan)

Photo by: Mark Lennihan

One World Trade Center, center, rises above the National September 11 Memorial and Museum at the World Trade Center, Thursday, Sept. 6, 2012, in New York. Tuesday will mark the 11th anniversary of the terrorist attacks of Sept. 11, 2001. The World Financial Center is on the left, and Four World Trade Center is at right. (AP Photo/Mark Lennihan)