Is New York's Ground Zero under siege by police?
4 December 2013 Last updated at 00:32 GMT
In New York, neighbours of the One World Trade Center, the skyscraper which has risen up over Ground Zero, have sued to protest what they say are the siege-like security measures in the area.
Even before the terror attacks on 11 September 2001, the old World Trade Center was struck by a truck bomb that killed six people. And police officials in New York say the security measures are necessary to protect the new complex.
The BBC's New York correspondent Nick Bryant spoke to people on both sides of the debate.
Produced by the BBC's Nada Tawfik, Anna Bressanin and Andrew Herbert
Altered States is a series of video features published every Wednesday on the BBC News website which examine how shifting demographics and economic conditions affect America on a local level.