Some of the world marked the 70th anniversary of the liberation of the Nazi concentration camp Auschwitz last week. The solemn observation included pledges that there must never be another Holocaust. We have reassured each other that the right lessons have been learned, with vivid reminders provided by some of the few survivors who still walk among us.

It’s not enough. We must act, and that requires more than a proliferating Twitter hashtag. Europe’s one million Jews are targets, easy targets, of the small cell and lone wolf radical Islamists like the ones who terrorized Paris last month. A march of more than a million men and women of goodwill through the City of Light was a striking image of unity, but it’s unlikely to dilute the virulence of what we face.

Our government should invite Europe’s Jews to move to the United States. With thousands of Jihadists making their way between homes in Europe and the lethal embrace of ISIS and Al-Qaeda in the war zones of the Middle East, the threat to their preferred victims will grow. The governments of Western Europe appear befuddled in their response to these bands of soldiers returning home from distant battlefields.

A comprehensive strategy to fight the enemy in Iraq and Syria has eluded the West. In this age of official euphemisms, it’s not clear how European governments will protect the soft targets and sensitive sites of terrorists. After the Charlie Hebdo newspaper and Hyper Cacher kosher market attacks in January, France deployed 10,000 troops to guard Jewish schools and other potential targets. Belgium did the same.

The January attacks in Paris were not France’s first taste of the malignant madness. A 2012 Jihadist attack on a Jewish school in Toulouse killed three students and a teacher. The world resumed its business.

There is no negotiating with these people. They will risk death avenging satire and attacking modernity. They will target soldiers–like Britain’s Lee Rigby, beheaded on a London street. Any infidel may do, but we know that their preferred target is Jews.

The West has been going soft on anti-Semitism. It was in full flower last year when the usual suspects on the left protested Israel’s right to defend itself from terrorist Hamas’ missiles launched from Gaza. Let’s remind the world that Jewish lives matter too.

Recent and distant history teaches us that the poison of anti-Semitism does not recede on its own. It grows worse. In the 1930s, we did not do enough to protect its victims as the Nazis made their intentions clear.

This time we can. We’ve done it for other refugees from hate and violence for centuries. We have provided refuge for Cubans fleeing their totalitarian masters for more than 50 years. America gave a reluctant embrace to Vietnamese boat people after the fall of Saigon 40 years ago. We accommodate and react to special circumstances.

Jewish generosity has aided millions of the bereft around the world. America can make room for European Jews in this escalating crisis. The indomitable Golda Meir declared, “Pessimism is a luxury that a Jew can never afford.” That was not an invitation to complacency. More than 7,000 from France immigrated to Israel last year. The Jewish Agency’s Natan Sharansky, who became well-acquainted with persecution in the Soviet Union, reports that 60,000 French Jews inquired about moving to Israel. Not every Jew, however, wants to live on the frontline that courageous Israel defends.

There are tens of millions of legal and illegal immigrants in the United States. Most of the thousands who would accept our invitation to find safety here would meet the various standards for ability, skills, professions and assets anyway. American life has been enriched beyond measure by Jews. This is no time to avert our gaze when they are under siege again. Open our doors and welcome them to America.