The site where the World Trade Center once stood is a grave site. Some bodies were never recovered since they were turned to dust. That dust is still there.
If a Dad says that the mosques) desecrate their son's grave site, doesn't he get a final say? In the end, what does it matter if Islam is peaceful and that the building they are planning is not offensive and good and all that.
End the end, it does not matter if the people who do not want the mosque build are "wrong" to protest it. If they feel it is wrong because of their wishes over their family members grave, they win the argument. Or am I missing something?
Suppose the religion that gave birth to japanese militarism wanted to build a shrine over the sunk ship in Pearl Harbor, would that be ok? Ok or not, if family members of the bodies still in the sunken ships protest it, should the government step in and build the shrine anyway?