For both the Seder and Remembrance Day raise the question of what is required for Jewish survival.The Haggada surfaces the issue largely through the “wicked son.” The danger, says the Haggada, is that that son positions himself as an outsider. Questioning Jewish tradition or Jews’ attitudes is perfectly legitimate. It is when Jews address the Jewish people as “you,” which the wicked son does, that they threaten Jewish survival. Our future rises and falls, to no small degree, on whether our children stand first with their own people.Jewish loyalty is going to become more critical – and challenging – in the years to come. I was in my mid-forties before I had my genuine first brush with anti-Semitism in the US. Most American Jewish kids have that “pleasure” much earlier. In all my years as an undergraduate at Columbia, I encountered not one instance of anti-Israel sentiment. The Jewish student groups were housed not far from the Muslim students; I cannot recall a single moment of unpleasantness.Back then, England’s prime minister was Margaret Thatcher. One could agree or disagree with her, but the headlines from Britain were not about Labor Party characters like Ken Livingstone, Naz Shah or Jeremy Corbyn. The world is changing – fast, and not for the better.From England to Greece to Austria, from Students for Justice in Palestine to BDS to hostile campuses across the United States, the world is rapidly becoming much more like the world in which my grandparents grew up. It is becoming hostile and mean-spirited, with Jews again in the crosshairs. We can weather this, but only if we stand together and place loyalty to the Jewish people first.The signs, though, are not good.Remember Joy Karega? She’s the assistant professor at Oberlin with the vile remarks accusing Israel and “Rothschild-led bankers” of bringing down a Malaysian airliner. She also posted a graphic of Jacob Rothschild that read “We own your news. The media. Your oil. And your government.” Marvin Krislov, Oberlin’s president, is Jewish. But even though Karega, who does not have tenure, could easily have been sent packing for such noxious postings, Krislov wrote to the Oberlin community that while he is the descendant of rabbis and even lost family in the Shoah, he “respects the right of its faculty, students, staff and alumni to express their personal views.”Noble. But when Jews defend the “right” of people to express “personal views” that accuse Jews of bringing down airliners and controlling the government, the Jewish people are in trouble. That’s the point of the “wicked son.”Krislov also has a right to his views, but the Jewish world can still make Oberlin feel the pressure. What would happen if a few Jewish alumni galvanized all Jewish donors to Oberlin and halted all contributions until Karega was gone? What Oberlin’s president was not willing to do, others must. Either we sanction people like Karega, or we fight them. There is no middle ground.When Husam El-Qoulaq, a student at Harvard Law School, recently asked Tzipi Livni why she was so “smelly,” the outcry was wall to wall. For having invoked the centuries-old trope of the “smelly Jew,” even other Muslim HLS students denounced Qoulaq. But not everyone did. HLS’s dean, Martha Minow (Jewish, and not long ago mentioned as a possible Obama nominee to the Supreme Court), refused to release Qoulaq’s name. Why? He had a right to what – privacy? Seriously? He has a right to conduct his job search (he’s in his final year of Harvard Law) without his noxiousness trailing him, despite his aligning himself with centuries of Jew-hatred? As if that were not sufficiently worrisome, after Qoulaq’s name was revealed, 11 Jewish HLS students wrote a public letter defending him. He was, they said, the “target of a vicious smear campaign,” a campaign with tactics that are “part of a sadly well-worn playbook aimed at discrediting and defaming those who dare challenge Israel’s abuses against Palestinians.”All good, except for one thing. Qoulaq did not ask Tzipi Livni anything about Israel’s conflict with the Palestinians. That would obviously have been legitimate.Instead, he chose a different road, an anti- Semitic road. And HLS Jewish law students saw fit to defend him. The Wicked Son, again – Jews rejecting the primacy of loyalty to their own people.And finally, Simone Zimmerman, who was for several minutes Bernie Sanders’s “Jewish outreach coordinator,” until she was dismissed after it was revealed that she had posted on Facebook comments such as “Bibi Netanyahu is an arrogant, deceptive, cynical, manipulative a**hole.”That coarse language, posted by someone with aspirations for public position, illustrated just childish instincts and poor parenting. Yet if many Israelis actually agree with her, was dismissing her just Sanders caving in to a right-wing Zionist apparatus that will allow no criticism of Bibi or of Israel? That is what Peter Beinart, defending Zimmerman, chose to imply. “If You Lose Simone Zimmerman, You Lose the Best of Jewish Millennials,” was the headline atop his Haaretz column. “I’m not worried about Simone Zimmerman,” he wrote towards his conclusion. “She’ll do fine. I’m worried about a community that punishes its children for challenging its lies.” I disagree with Beinart (not the first time, of course – and we’ll be debating each other once again in Tustin, California, on September 11, so we can discuss this further then). Why? Because I think we should hide our lies? Because the Zionist camp should be monolithic? Because I’m a huge Bibi supporter? Obviously not.It’s because I think that while criticism of Israel is entirely legitimate, when such critique denies the fact that Israel faces real enemies, it crosses a line.In 2015, Zimmerman posted on Facebook, “F*** you, Bibi… you sanctioned the murder of over 2,000 people this summer.”Murder? Whatever one thinks of Netanyahu’s conduct of the 2014 Hamas Gaza War (and many Israelis who usually dislike Netanyahu thought that summer was one of his rare statesmanlike periods), to say that Bibi “murdered” 2,000 people is to suggest that Hamas represented no threat to Israel. Or that Israel’s citizens near Gaza should continue to live in fear and with terrorist tunnels. Or that Israel and Jews have no right to defend themselves.When someone claims that Jews have no right to defend themselves, we ought to recall – especially on this week of Holocaust Remembrance Day, when we are reminded of how little we can count on others to defend us – they cross a line back into a dark period of Jewish history. One of the points of Jewish sovereignty, which the international community understood for a few brief moments in the 1940s, is that Jews have a right to self-defense. Zimmerman’s “sin” was that she denied Jews that right. She thus positioned herself as an enemy of the progress that Jews have made. She had to go.To survive, Jews need instinctive loyalty to Jews. Caring about other peoples and defending them are also prime Jewish commitments; but when Jews are under attack, a long-standing instinct that has kept us going has been the instinct of loyalty. That so many prominent Jews do not understand that is a sad indication of to where we have come. Even more ominously, it may indicate where we are headed. The writer is Koret Distinguished Fellow and chairman of the core curriculum at Jerusalem’s Shalem College. His new book, Israel: A Concise History of a Nation Reborn, is forthcoming in October from Ecco/HarperCollins.