A Prelude to Murder: Calling Humans Vermin

This op-ed was originally published in the Wall Street Journal.

Before the Nazis murdered six million Jews, they called them rats and vermin. Before the 1994 genocide in Rwanda, Hutu leaders declared that all Tutsi men, women and children were inyenzi, cockroaches. Today, similarly dehumanizing language is surging in countries like Burma, Greece, Nigeria and Iran—and history teaches that it can inspire mass violence if left unchecked.

Such inflammatory speech is launched from a variety of platforms: newspapers, broadcasts, pulpits, the Web, and even text messages. It's the content that's strikingly similar. In dozens of languages, human beings are described as less than human. The inciters say these pests must be eliminated as a matter of self-preservation.

In Burma, a Buddhist monk who leads the nationalist 969 Movement has compared the country's Muslim minority to "mad dogs" and African carp that "breed quickly" and are "very violent." Last March, Buddhists rampaged through a Muslim community in the city of Meiktila, torching houses and killing more than 20 people including children. The monk, Wirathu, called the violence "a show of strength."

In Greece, the fascist group Golden Dawn has risen in the past few years from a fringe group to a political party with 18 seats in parliament. It ran on a platform promising to "rid Greece of the stench" of immigrants. Ilias Panagiotaris, a Golden Dawn parliamentarian, vowed at a rally before the June 2012 election that the group would "carry out raids on hospitals and kindergartens and it will throw immigrants and their children out on the street so that Greeks can take their place." Golden Dawn members have indeed carried out beatings and stabbings. Since the 2012 election, 71 violent attacks have been attributed to Golden Dawn according to the country's ombudsman—including the fatal stabbing in September of the antiracist rapper Pavlos Fissas.

In Nigeria, ongoing violence between Christians and Muslims has been fueled by inflammatory messages from both communities. In 2010, in the city of Jos, text messages warned Christians not to buy food from Muslims "because it was poisoned." Hundreds of people were killed in subsequent riots. Since 1999, more than 14,000 people have been killed in such interreligious violence, according to the U.S Commission on International Religious Freedom.

Then there is Iran, a country where dehumanizing speech is coming directly from the government itself. In a speech Supreme Leader Ayatollah Ali Khamenei delivered to the Basij paramilitary organization on Nov. 20, he returned to tropes that have long been a staple of Iran's leading religious and political figures. Mr. Khamenei referred to Israeli Prime Minister Benjamin Netanyahu as a "rabid dog" and attacked European leaders for supporting Israel. They are "cringing before this creature," he said, "which is not worthy of the name of a human being, before these leaders of the Zionist regime, who look like beasts and who cannot be called human."

Such cases challenge leaders around the world who should be aware by now that speech can catalyze not just violence, but genocide.

Some countries respond with either censorship or punishment. Greece, for example, is attempting the latter with a proposed law against hate speech. But this won't solve the problem. Prosecuting extremist speakers can simply amplify their messages, and it's nearly impossible to suppress speech now that it spreads so quickly online.

A better method is for influential leaders to rebuke inflammatory speakers unequivocally and publicly. Yet neither foreign nor local leaders have forcefully condemned this incendiary rhetoric in a single one of these cases. Leaders in Burma, for instance, have been silent about torrents of anti-Muslim speech, even after they have been followed by killings.

Emphatic "counter-speech" may work. In Kenya, after months of inflammatory speech by politicians and community leaders pitting members of the Kikuyu, Luo and Kalenjin tribes against one another, and a disputed election in late 2007, violence broke out and more than 1,000 people were killed. When the country held its next presidential election on March 4, 2013, Kenyan leaders—political, religious, cultural and even athletes—spoke out against violence and violent speech. Despite another tense, close race and disputed results, there was no eruption of violence.

Directly confronting purveyors of hate and dehumanization offers the best hope of stopping the language that can escalate into physical violence. The responsibility to do so is one that leaders of all stripes, not just government officials, must not shirk.

Ms. Benesch founded the Dangerous Speech Project, and serves as the Edith Everett Genocide Prevention Fellow at the United States Holocaust Memorial Museum. Mr. Abramowitz directs the Museum's Center for the Prevention of Genocide.