Klinghoffer opera attracts hundreds of protestors
Politicians including former New York Mayor Rudy Giuliani demonstrated outside the Metropolitan Opera on Monday over a controversial show.
John Adams' opera The Death of Klinghoffer relates the murder of a disabled Jewish man killed by Palestinian gunmen in 1985.
Some critics have accused the work of glorifying terrorism and being anti-Semitic.
The Met denies these claims. The opera will run in New York until 15 November.
About 400 people stood behind barricades chanting: "Shame on the Met!" and carrying signs saying "The Met glorifies terrorism" before the first scheduled performance.
Giuliani and Republican politician Peter King gave speeches to the demonstrators.
Giuliani said he wanted to warn people the Klinghoffer opera "is a distorted work".
"If you listen, you will see that the emotional context of the opera truly romanticises the terrorism... and romanticising terrorism has only made it a greater threat," he said.
The demonstration is part of an on-going protest which began on 22 September when the Met's season opened with a work by Mozart.
One placard at Monday's protest read: "We pray for Leon Klinghoffer's soul."
Rabbi Avi Weiss told the Associated Press news agency: "The language is explosive. It's radioactive. It's dangerous. It inspires violence."
The Met had originally planned to relay the revival - a co-production first seen in London in 2012 with the English National Opera - live to cinemas around the world.
But after Jewish groups argued the screenings would stoke anti-Semitism outside the US, the broadcasts were cancelled.
The Met's general manager, Peter Gelb, told the BBC: "There's no doubt for anyone who sees this opera that… it's not anti-Semitic. It does not glorify terrorism in any way. It is a brilliant work of art that must be performed."
Gelb, who has been with the Met since 2006, acknowledged the strength of feeling surrounding the opera - which premiered in Brussels in 1991 - and said he had received death threats.
But, he continued, "at the end of the day, anyone with any sense of moral understanding knows this opera is about the murder of an innocent man".
Klinghoffer's daughters, Lisa and Ilsa Klinghoffer, issued a statement included in the Met's programme for the opera.
It said they believed the arts "can play a critical role in examining and understanding significant world events".
"The Death of Klinghoffer does no such thing. It presents false moral equivalencies without context, and offers no real insight into the historical reality and the senseless murder of an American Jew."
Advertising for the opera comes with the slogan: "See it. Then decide."