In 1933, Nazi propaganda began depicting Jews as vermin carrying diseases like typhus. By the end of the Holocaust 12 years later, 6 million Jews had been killed by their neighbors.

In 1994, Rwandan radio and newspapers labeled the Tutsi people "cockroaches" and called for stamping them out. A hundred days later, nearly a million people had been killed by their neighbors.

Since 9/11, the Department of Justice has investigated more than 11,000 incidents of anti-Muslim rhetoric threatening to incite violence in the U.S., resulting in 45 prosecutions.

Political candidates and supporters call for walls, national registries of Muslims, isolating Muslims into ghettos and banning Muslims from entering this county. A week after the Paris attacks, 25 U.S. governors had spoken against accepting Syrian refugees into their states. People who are frightened by an unpredictable economy, a high-tech world, and changing norms for social and sexual behavior are susceptible to this hateful rhetoric.

The First Amendment allows this speech to flourish, but not hateful acts.

At a Texas mosque, vandals tore pages of a Qur'an and covered them with feces. In New York, a man punched a Muslim store owner and yelled, "I kill Muslims." In California, a woman shouted anti-Islamic slurs and threw hot coffee at Muslims. A pigs' head was found outside a mosque in Philadelphia. A man confronted a Muslim woman at a New York City bus stop and said, "I can't wait for the U.S. to get rid of you trash." Windows were broken at a Phoenix mosque. A man set fire to a Somali restaurant in Grand Forks, N.D.

Hateful acts are occurring from California to New York, North Dakota to Texas.

What about Minnesota?

During prayers at a St. Cloud mosque, congregants' car windows were smashed. In St. Paul, "[expletive] Islam" was written on a driveway in a neighborhood with several Muslim families. A Minnesota vanity license plate had the same slogan. Muslim children in Minnesota schools are bullied. A Minnesota woman smashed a Muslim woman in the face with a beer mug for speaking Swahili at an Applebee's in Coon Rapids. A Minnesota attorney was verbally assaulted at a Vikings game by an angry fan who feared that the attorney was a refugee and, therefore, a terrorist.

The FBI Hate Crime Statistics report for 2014 documented 1,140 victims of anti-religious crimes. One in five of those had an anti-Muslim bias.

In 2013, Minnesota passed a law designating April as Genocide Awareness and Prevention Month. Genocides don't begin overnight with mass extermination. The process is one of slow, steady, inexorable steps into violence, and it begins with rhetoric of hate. In April, a month to recognize injustice, we must reflect on hate happening in our own country.

More than 60 percent of religiously motivated crimes in the FBI Hate Crimes database are perpetrated against Jews. As a Jew growing up soon after the Holocaust, I'm terrified of today's Islamophobia. It can pivot and turn onto any group — Jews, blacks, gays, transgender people, anyone — with the potential for horrific violence.

My good friend Mariam Mohamed, who wears a hijab, told me that she's now afraid to walk outside.

What have we become?

Immigrants, refugees and others in our neighborhoods who feel unwelcome should know that many of us believe we are one.

The St. Paul-based World Without Genocide organization and the St. Paul Department of Human Rights and Equal Economic Opportunity are holding a metrowide event — free and open to all — at the St. Paul RiverCentre on Sunday, April 24 from 1 to 3 p.m.

Nearly 60 organizations representing government, faith communities, civic and business associations, human rights organizations, and educational institutions are cosponsors. Our theme is "We Are One: Standing United in Celebrating Community." There will be music, song, refugees' video testimonies, food and welcoming words from Minnesota state Senate President Sen. Sandy Pappas, DFL-St. Paul, as well as St. Paul Mayor Chris Coleman — and my friend Mariam.

Ellen J. Kennedy is executive director of World Without Genocide at Mitchell Hamline School of Law in St. Paul. (www.worldwithoutgenocide.org)