But some protesters at this rally in Fort Lauderdale, Fla., took their rhetoric a step further, calling for the extermination of Israel — and of Jews.
Separated by battle lines and a stream of rush-hour traffic outside a federal courthouse last week, at least 200 pro-Palestinian demonstrators faced off against a smaller crowd of Israel supporters.
Most of the chants were run-of-the-mill; men and women waving Palestinian flags called Israel's invasion of Gaza a "crime," while the pro-Israel group carried signs calling the Hamas-run territory a "terror state."
But as the protest continued and crowds grew, one woman in a hijab began to shout curses and slurs that shocked Jewish activists in the city, which has a sizable Jewish population.
"Go back to the oven," she shouted, calling for the counter-protesters to die in the manner that the Nazis used to exterminate Jews during the Holocaust.
"You need a big oven, that's what you need," she yelled.
• Click here to see video from the protest.
Millions of Jews were gassed and burned in crematoria throughout Europe during Adolf Hitler's rule of Germany. The protest organizers, asked to comment on the woman's overt call for Jewish extermination, said she was "insensitive" but refused to condemn her statement.
"She does not represent the opinions of the vast majority of people who were there," said Emmanuel Lopez, who helped plan the event, one of many sponsored nationwide on Dec. 30 by the ANSWER (Act Now to Stop War and End Racism ) Coalition.
Lopez, a state coordinator for ANSWER, admitted there is a problem with anti-Semitism within his organization's ranks. But then he went on to call the supporters of Israel across the street "barbaric, racist" Zionist terrorists.
"Zionism in general is a barbaric, racist movement that really is the cause of the situation in the entire Middle East," Lopez said.
The unidentified woman, who protest organizers said was a Muslim, wasn't the only protester who raised hackles that day. Other demonstrators held signs that said "Nuke Israel," and a number made comparisons to the Holocaust, accusing Israel of genocide in Gaza.
More than 670 Palestinians, including hundreds of civilians, have been killed in the 12 days of Israel's campaign in Gaza. At least 30 were killed Tuesday by Israeli shelling of a U.N. school that had been housing refugees. (Israel said its forces fired at militants who launched mortars from that location.)
"This is absolutely inhumane," said Ahmed Suid, who attended the demonstration, according to the South Florida Sun-Sentinel. "This is a modern-day Holocaust."
The comparisons of the Israelis to the Nazis has Jewish organizations concerned about a "growing trend" at protests in America, where they say hatred of Israel and Jews is being increasingly preached.
"We're worried about hate speech. We're worried because hate speech eventually leads to pain and suffering and death," said Abraham Foxman, director of the Anti-Defamation League, which has been tracking Gaza protests.
"Comparisons of Israel to the Nazis are a deeply cynical perversion of history, an attempt to turn the tragedy that befell the Jewish people into a bludgeon against Israel," he said.
Even though police had to intercede and break up a potentially violent confrontation between the two factions at the Fort Lauderdale protest, organizers called it a success, saying it drew crowds of new activists.
"It was not just an academic exercise . . . not just a protest," Lopez told FOXNews.com. "It's a material force."
Click here for the full video from YouTube.
YOU DECIDE: Did demonstrators cross the line?
