Antisemitism is on the rise once more amid ongoing Israel-Hamas war, experts say

Officials have repeatedly sounded the alarm on the rise of antisemitism in recent years, and the ongoing war in the Middle East between Israel and the terrorist group Hamas appears to have incited a new wave of threats against Jewish communities in the United States, experts said.

"We know invariably when tensions flare in other parts of the world, the reverberations are felt everywhere, including in our homes and our communities," said Melanie Pell, chief field operations officer of the American Jewish Committee. "So we're really bracing for a very vulnerable time and thankfully, law enforcement is paying very close attention and is in constant coordination and collaboration with the Jewish community."

At least 1,400 people have died and 4,629 others have been injured in Israel, according to Israeli authorities, since Oct. 7, when Hamas launched its surprise attack on Israel. In the neighboring Gaza Strip, at least 9,061 people have been killed and more than 23,000 have been injured, according to the Hamas-controlled Gaza Health Ministry.

Experts and federal law enforcement agencies have been warning about the impact of antisemitism and extremism for years.

In 2022, before the current Israel-Hamas war, the FBI said it tracked 1,124 reported hate crimes directed at Jewish people or institutions in the U.S. It's the highest number of anti-Jewish crimes since 1993, according to the FBI data.

Antisemitism in the mainstream

In the past few years, the rise of vocal neo-Nazi and white supremacist groups both online and in the streets as protesters -- as well as the use of antisemitic rhetoric by some celebrities and politicians -- has propagated the hateful rhetoric in the mainstream, experts say.

In November 2022, former President Donald Trump had a dinner with prominent white nationalist and alleged Holocaust denier Nick Fuentes, as well as rapper Ye, formerly known as Kanye West, who has been criticized for promoting antisemitic conspiracies.

However, Trump played down his involvement with Fuentes, insisting he didn't know who Fuentes was before they met and that he was unaware Fuentes would be joining the meal.

"This past week, Kanye West called me to have dinner at Mar-a-Lago. Shortly thereafter, he unexpectedly showed up with three of his friends, whom I knew nothing about," Trump said in a statement at the time.

Jews have also long been the subject of conspiracy theories, including "replacement theory," which has been seen as the motivation behind several mass shootings targeting marginalized communities -- including in Buffalo, New York, where 10 people were shot and killed at a supermarket in the heart of a Black community.

"Great Replacement theory is the notion that people from minority populations, both here and in Europe, are replacing the existing white, largely Christian [population]," Larry Rosenthal, lead researcher of the Berkeley Center for Right-Wing Studies, told ABC News in a past interview.

Antisemitism frequently charges Jews with conspiring to harm humanity, and it is often used to blame Jews for "why things go wrong," according to the U.S. Department of State.

However, the department states in its working definition of antisemitism that criticism of Israel's government, "similar to that leveled against any other country," cannot always be regarded as antisemitic.

The Israeli government has received criticism for the unfolding humanitarian crisis in Gaza amid Israel's retaliation against Hamas, which the U.S. government has designated a terrorist organization.

Officials have called white supremacists and other far-right-wing extremists the most significant domestic terrorism threat.

"Racially or ethnically motivated violent extremists, including white supremacists ... will likely remain the most lethal [domestic violent extremists] movement in the Homeland," Homeland Security Secretary Alejandro Mayorkas said in a 2021 statement to senators to provide an assessment of the current threats to the nation.

Acts of violence

Repeated instances of hate and antisemitic attacks have amped up fears in Jewish institutions and communities, prompting heightened security, as well as safety training. It has also put federal agencies on high alert.

In 2017, alt-right neo-Nazis and white supremacists marched through Charlottesville, Virginia, holding lit tiki torches and chanting Nazi-related phrases such as "blood and soil" and "Jews will not replace us" at a "Unite the Right" rally.

The tensions turned deadly when a 20-year-old Ohio man allegedly accelerated his car into a crowd of counter-protesters, killing 32-year-old Heather Heyer and leaving 19 others injured, five critically.

In 2018, the Tree of Life Synagogue in Pittsburgh, Pennsylvania, became the site of a mass shooting in which a white nationalist shot and killed 11 members of the congregation. Robert Bowers was convicted in June on all 63 charges against him, including 11 counts of hate crimes resulting in death.

In 2022, pro-Nazi protesters waving Nazi flags or shouting hate speech were seen in front of two separate Georgia synagogues in what was just one instance of hundreds of targeted anti-Jewish hate incidents.

That year, the FBI also announced a warning about a "broad threat" to New Jersey synagogues and urged people to "stay alert" and "take all security precautions." The man who allegedly posted the threat told the FBI he is angry and dislikes Jewish people, but had no plans to do anything harmful.

"By seeking to turn the masses against the few, by scapegoating and dehumanizing others -- and most of all -- by stoking violence, the perpetrators of hate aim to upend our most cherished values and undermine our efforts to build a culture of respect, peace and cooperation," President Joe Biden said in May when he announced the U.S. National Strategy to Counter Antisemitism.

"Protecting the Jewish community from antisemitism is essential to our broader fight against all forms of hate, bigotry and bias -- and to our broader vision of a thriving, inclusive and diverse democracy," he said.

Amid the current tensions overseas, federal agencies have warned Jewish, Muslim and Arab communities alike about the increase in threats seen against cultural and religious institutions, as well as individuals.

Last month, an Illinois man was charged with stabbing a 6-year-old Muslim boy to death and seriously injuring his mother in what police said was a hate crime linked to the ongoing conflict between Israel and Hamas in the Middle East.

The suspect has pleaded not guilty in the fatal stabbing of the boy. Law enforcement agencies across the U.S. have implemented strategies to tackle the climate of fear -- including sending an increased police presence to cultural and religious institutions.

"There is a lot of anxiety, there is a lot of deep sadness ... and also profound resilience," Pell said. "We are a community. We are a people that has endured. We will make it but this has been a really profoundly challenging, challenging moment."