In the span of a month, we’ve seen thousands of protesters in London chanting anti-semitic slogans,  posters commemorating Jewish victims of Hamas atrocities ripped down, and the Weiner Holocaust Library’s signage defaced. 

According to the Community Security Trust, there has been a 537% increase in hate incidents across the UK. Over half of those have taken place in the nation’s capital, London. 70% of incidents were “online,” but the figure also includes 47 assaults, with others including the targeting of children and schools. 

As U.S.-based researchers of antisemitism, these figures are a cause for sadness but not surprise. Our own research corroborates the events of the past month — the connection between online hate speech and antisemitic violence — leading to serious questions around what constitutes the boundary between hate and free speech.   

Earlier this year, we released a study of the physical and online antisemitism after Israel’s May 2021 operation against Hamas in Gaza. With our partners at the New York-based Network Contagion Research Institute, we analyzed literally billions of comments from Twitter and Reddit and hundreds of antisemitic incidents. 

Soon after the 2021 war began, vitriolic anti-Israel and anti-Jewish campaigns spiked. The hate began online, with severe condemnation of Israel’s efforts to root out the terrorism in Gaza and its impact on civilians. 

To be clear, Israel’s policies and tactics should always be open to scrutiny, just as any nation should. However, the intense hateful language normalized antisemitic sentiments. It spilled into protests, feeding those groups already disposed to violence.

From the start, the protests were not about questioning Israel’s policies but its very existence and the right of Jews to live anywhere between the Jordan River and the Mediterranean Sea, just as we are seeing this year. 

Critics relied on language that was couched in terms of human rights but, in reality, demonized and created unprecedented double standards directed at Israel. 

On social media, Jews were painted as white-supremacist colonial settlers oppressing an indigenous ethnic minority. Very quickly, we saw that by employing these false labels, Israel wasn’t just accused of apartheid; on Twitter, apartheid came to mean Israel exclusively.

The weaponisation of online rhetoric correlates strongly to weapons being wielded in public. Germany saw seven reported antisemitic incidents a day in 2021 and more incidents were recorded in the UK than in any year since it began tracking them in 1984. 

The 2021 war in Gaza lasted just a few weeks. The events of the last month show that while it receded, it remained dormant. If 2021, was an ugly harbinger of what we are seeing now, it also points to what lies ahead, during what will be a protracted war with powerful images of casualties on both sides. 

We already saw that trend when Israel was falsely accused of bombing a hospital in Gaza. The angry words online came just before a worldwide “day of rage” which led to attacks like a Berlin synagogue firebombing. Germany’s Central Council of Jews described it as “psychological terror that leads to concrete attacks.” 

Antisemitism is a millennia-old scourge

Antisemitism is a millennia-old scourge. We are not naive enough to think that recognizing and understanding the lessons from 2021 will eliminate it in 2023. But we hope the research can provide specific lessons and guideposts.

For starters, administrators and CEOs from universities to corporations globally must move beyond the cautious statements of the past few weeks to call out hate and proactively protect Jewish community members, the way the Prime Minister Rishi Sunak has done. 

The hate we are seeing globally is both predictable and real. The long tail of antisemitism after the war could last years. We may not be shocked. But we need to be prepared.