Opponents of the proposed Ground Zero mosque in New York City will have their day in front of the New York State Supreme Court Tuesday.

The class action lawsuit was filed by a group known as Freedom Watch on Behalf of Vincent Forras - who was a First Responder during the Sept. 11, 2001 terror attacks.

Imam Feisal Rauf is the backer of the Ground Zero mega-mosque. He has called the mosque opponents "enemies of Islam."

But Forras and Freedom Watch say the imam and his mosque are the real threat.

"We say this is a nuisance if it increases the threat of terrorism in the neighborhood. The imam says, 'If I don't get my mosque, there's going to be terrorism here.' So that's a threat," explained Larry Klayman, the president of Freedom Watch and the attorney representing Forras.

"Also, it raises the tax rate in New York City and in that neighborhood," he added. "It raises to cost to the people of New York to have to defend that mosque. Why should we have to pay to protect the imam? We're not a threat to the imam, it's quite the contrary," Klayman said.

Opponents of the Ground Zero mosque say it's a deliberate thumb in the eye to the U.S. and 9/11 victims, and a symbol of Islamic domination.