Thousands Mourn in NY, DC, Penn.

    Visitors to the National September 11 Memorial walk below the rising towers 1 World Trade Center, left, and 4 World Trade Center, Monday, Sept. 10, 2012 in New York. Tuesday will mark the eleventh anniversary of the attacks of Sept. 11, 2001. (AP Photo/Mark Lennihan)

    Mark Lennihan / AP Photo

    President Obama visited the Pentagon to mark the anniversary of 9/11 Tuesday, saying, "This is never an easy day." Thousands gathered to mourn in New York, Washington, D.C., and Pennsylvania. Meanwhile, construction will resume at the National September 11 Memorial & Museum after the museum and the Port Authority came to an agreement Monday. All work at the memorial was halted last year over disagreements about funding, financing, and oversight. The federal government also announced it will add cancer to the list of illnesses linked to 9/11—making many former  Ground Zero workers eligible for financial compensation.

    Read it at NBC New York