The ROP loves to build a mosque right on the site of a 'conquest'. The Dome of the Rock - a coincidence? No, of course not. Look at the Temple of Karnak in Egypt with a mosque built right inside it, Coincidence? No, of course not. It is important to understand Islamic thinking. A mosque at Ground Zero would be a permanent middle finger raised to New York and America.
Those who do not understand this are either extremely stupid or craven cowards. Some groups - politicians - can be both at the same time. Ask yourself "Why are churches, cathedrals and synagogues NOT ALLOWED in Saudi Arabia" (and it is not because our beloved allie, the Saudis might be offended).