Photo by: Mark Lennihan

** FILE ** In this April 17, 2012, photo, One World Trade Center, now up to 100 floors, rises above the Manhattan skyline in New York. On Monday, April 30, One World Trade Center — being built to replace the twin towers destroyed on 9/11 — gets steel columns to make its unfinished framework a little higher than the Empire State Building's observation deck, to become the tallest building in New York. (AP Photo/Mark Lennihan)