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In Europe, the fight over Israel’s war against Hamas in Gaza has prompted violent street battles, firebombs thrown at synagogues and even a mid-game attack against a visiting Israeli soccer team by protesters in Austria.

In America, it has been more a battle of commentary, slogans and demonstrations.

Pro-Palestinian demonstrators protest across the street from a pro-Israel rally in Chicago, Ill., on July 28. photo/jta-getty images-scott olson

There were 134 anti-Israel demonstrations in U.S. cities during the first 15 days of the conflict that began July 8, according to the Anti-Defamation League. California led the nation in anti-Israel agitation (see story, 2), followed by New York, Ohio, Washington state and Texas, the ADL said.

At many pro-Palestinian demonstrations, the ADL has documented comparisons of Israel to Nazi Germany, such as a placard at a protest in New York that read, “Jerusalem 2014 smells like Berlin 1939… #Zionazism.”

Paul Goldenberg, national director of Secure Community Network, the American Jewish communal security initiative, said that at first he was concerned that anti-Israel protests in the United States might turn violent, but that hasn’t happened.

“I would say at this juncture we are cautiously optimistic that we will not see the type of violence we have seen in Europe,” he said. “People need to continue going to synagogue, going to federations, going to their community centers. At this point there’s no imminent or specific threat we are aware of.”

There have been a few cases of anti-Semitic vandalism related to the Gaza conflict.

On July 28, an Orthodox synagogue in North Miami Beach, Fla., Congregation Torah V’Emunah, found a swastika and the word Hamas scrawled on the outside of the building. A day earlier, cars owned by a Jewish family in Miami Beach were egged, smeared with cream cheese, and defaced with graffiti reading “Jew” and “Hamas.”

In Malibu, graffiti reading “Jews=Killers” and “Jews are Killing Innocent Children” appeared near the entrance to a Jewish summer camp. Pro-Palestinian graffiti was sprayed on a Chabad center in Las Vegas and on an Orthodox synagogue in Lowell, Mass.

Last week, Jewish Voice for Peace, an organization focused on criticizing Israel’s treatment of the Palestinians, organized a “die-in” outside the New York office of the Friends of the Israel Defense Forces.

Meanwhile, pro-Israel supporters took to the streets in a variety of U.S. cities to voice support for Israel’s actions in Gaza. Pro-Israel rallies in New York and Chicago July 28 drew thousands of Israel supporters, including U.S. senators and representatives.

A Gallup poll conducted July 22-23 showed that younger Americans are much less likely than older Americans to view Israel’s actions against Hamas as justified. Fifty-five percent of those over age 65 said Israel’s actions were justified, compared with 53 percent of those between 50 and 64; 36 percent of those 30-49, and 25 percent of those 18-29.

Many of the battles in the United States over Israel have taken place in cyberspace. Use of the Twitter hashtag #Hitlerwasright has soared since the launch of Israel’s operation in Gaza, according to the ADL.

The website of Congregation Beth Am Israel, a synagogue in Penn Valley, Pa., was hacked, with the homepage replaced by images of Mohammed Abu Khdeir, the Palestinian teenager killed in Jerusalem in early July by Jewish extremists.

With the Gaza conflict now in its fourth week and Israeli Prime Minister Benjamin Netanyahu vowing to press on until all Hamas’ tunnels into Israel are destroyed, security expert Goldenberg says the greatest security concern for American Jews should be the prospect of so-called lone wolf attacks.

“My concern is as this goes on: It’s that lone wolf — the individuals that are being inspired by the Internet or media as the media attention continues on the casualties in Gaza — that may become inspired to act much more violently,” he said. “If you see something, say something.”

JTA’s Miriam Moster contributed to this report.