The cover of a Koran. Photo: Wikimedia Commons.

At the end of World War I, a soon-to-be released German corporal was tasked by his superior to write a memo about the threat of Jews to Germany’s future.

This is what he came up with:

Anti-Semitism — born of purely emotional grounds — will find an expression in the form of pogroms. … The final goal must be the removal of the Jews. To accomplish these goals, only a government of national power is capable, and never a government of national weakness.

It was written and signed by Adolf Hitler.

Twenty years later, he launched World War II, and Nazi Germany’s systematic genocide would eradicate 6 million Jews. Hitler’s letter is now on permanent display at our Museum of Tolerance, a brutal warning that when someone threatens to kill you, you must take them seriously.

That’s why the Simon Wiesenthal Center is urging both the Department of Homeland Security and the US Attorney in California to investigate Imam Ammar Shahin’s recent sermon at the Islamic Center of Davis. In his remarks, he said that Muslims — everywhere — are obligated to slaughter all Jews — everywhere. 

“The Prophet Muhammad said: ‘Judgment Day will not come until the Muslims fight the Jews…’ …. Oh Allah, liberate the Al-Aqsa Mosque from the filth of the Jews. … Oh Allah, count them one by one and annihilate them down to the very last one. Do not spare any of them. … Oh Allah, make this happen by our hands. Let us play a part in this. Oh Allah, let us support them in words and in deeds. Oh Allah, let us support them in words and in deeds. Oh Allah, let us support them in words and in deeds.” (Translation courtesy of MEMRI.)

There is no known cure for terrorism, but we know how the disease takes hold. Recruitment takes place via social networks or via face-to face indoctrination. Fanatic clergy like Imam Shahin and Mahmoud Harmoush, who delivered a similar screed in Riverside, California, on the very same day, play an outsized role in inciting true believers against Islam’s “enemies.” It’s not just about Jews and synagogues. Massacres of tourists in London, concertgoers in Manchester, Christian clergy in Normandy and innocents in Paris, Brussels, and San Bernadino, prove that jihadists see enemies everywhere.

So what can be done?

In Canada, police served an arrest warrant against Jordanian Sheikh Muhammad bin Musa Al-Nasr for willfully promoting hate when he invoked the same hadith as Shahin, calling for the murder of Jews during a sermon in Montreal.

Hate speech is generally protected in the US, but not when it can be shown to be “inciting imminent lawless action.” Shahin’s call to kill Jews comes at a time when FBI statistics confirm that American Jews are the number one target of religion-based hate crimes. Terrorists around the world have heeded other extremist clergy’s calls to kill in God’s name. Shahin’s threat is “imminent” enough to warrant action.

When targeting religions, the theologically-validated hatred of the Muslim Brotherhood, Al-Qaeda and Al-Shabab knows no bounds.

Remember the 2015 ISIS video showing the beheading of 21 Coptic Egyptians, identified as “people of the cross, followers of the hostile Egyptian Church.”

Yet, the Obama administration balked at acknowledging that the victims were targeted because they were Christians, referring to them only as Egyptian “workers.” For years, the US, fearful of sparking a holy war, turned a blind eye to the religious fanaticism that plays a key role in this struggle.

But that holy war is already here. The Davis imam followed the same jihadist script that has spawned terrorism and mayhem on every continent. If he isn’t jailed for incitement to mass murder, his parishioners and the public should banish the bigot.

If his mosque stands behind Shahin’s murderous calls, then the IRS should re-evaluate its charitable status.

Shahin’s screed came just as a group of 60 courageous imams from Belgium, France, the UK and Tunisia participated in a peace march. They prayed at the sites where jihadists butchered innocents. Voices like theirs should be given prominence everywhere, starting with San Bernadino and Davis, California.

Shahin’s screed also challenges both President Trump’s and previous administrations’ immigration policies. How many more people who carry the same hatred driving Shahin got through the old vetting process? Shahin is from Egypt, a country not on President Trump’s list. This isn’t just a threat to Jews. Young people indoctrinated to a culture of death represent a threat to virtually anyone-including other Muslims who don’t embrace their jihadist worldview.

The two imams’ attacks, both delivered at mosques near two University of California campuses, could have incited extremists to start a “holy war.” Thus, we hoped for condemnation of these attacks. Yet for one week, there was wall-to-wall silence, except for those groups endorsing an intifada against Israel for the Jewish state’s audacity in installing metal detectors after murderous gunfire at the Temple Mount. Last Friday, MPAC released a statement stating that it was “disturbed” by the sermon of Imam Shahin. The Davis imam finally apologized at a press conference. He apologized for the “hurt” he caused, but did not distance himself from the controversial hadith used by extremists as a license to kill.

And what about their other leaders? Could it be that some silently cheer bigoted pulpit thumpers? How many actually believe that the God of Abraham sanctions the murders of Jews and Christians?

After Davis — despite a belated apology — nobody can say for sure.

Rabbi Abraham Cooper is associate dean and director of global social action for the Simon Wiesenthal Center. Rabbi Yitzchok Adlerstein is the director of interfaith relations for the Simon Wiesenthal Center.