The Jewish students at UCLA will never forget the night of February 25, 2014. For 13 nightmarish hours, they were confronted with the hateful words and wild eyes of hundreds of fellow students — supporters of the boycott, divestment and sanctions movement — who alleged that defending Israel was tantamount to defending racism, genocide and infanticide. For one long night they experienced a debate on boycotting Israel that turned into a horror show of persecution.

They had not been prepared for such a near-violent conflict, and many of them were emotionally wounded. Thus when the vote — on whether the university should divest of companies that ostensibly profit from the occupation — went narrowly in their favor, they felt no sense of triumph; on the contrary. More than a hundred students left the meeting at dawn, hugged each other on a campus lawn and cried.

In recent months I have visited 27 American universities. I did not come to preach, but to listen. I tried to conduct an open, candid dialogue with the sons and daughters of a new Jewish generation that faces a challenge their parents and grandparents never did. Day after day I sat for entire days with groups of Jewish students — more than 100 groups in all — and asked them to share with me what was on their minds and in their hearts.

In Hillel houses at Princeton, Brown, Yale, Dartmouth, Michigan, Northwestern, the University of California San Diego and 20 other campuses, I repeatedly heard variations of the same heartbreaking story: Jewish students who (still) love Israel and (still) feel close to it, but who are asking tough ethical questions that Israel has no answers for. These are students facing near-overt anti-Semitism who themselves have harsh questions about the Jewish state that the Jewish establishment forbids them to express.

Thousands find themselves in a very tough jam. In front of them are professors and students who argue that Israel is Goliath, but behind them there’s no Israel proving that it is a David.

We feel like we’ve been abandoned on the battlefield, many of them told me. The anti-Zionists, they said, are accusing us of collaborating with evil, but Zionism doesn’t understand us and doesn’t speak to us; instead, it’s busy building more and more and more settlements.

That’s why their internal struggle is so agonizing and their pain so deep. That’s why many of their in-depth conversations with me came to tears, too.

The contemptible, sophisticated and well-oiled offensive by the BDS movement is a strategic threat to Israel. If it isn’t halted, it could position the democratic Jewish state as the South Africa of 2020. But the real existential threat facing the Jewish people is the increasing tension between the liberal identity of most young American Jews and the distorted image of Israel as an unjust oppressor and occupier.

As a result of this tension, some come out against Israel, some are confused and many are simply indifferent. For too long, the right has been telling these young people that everything here is great – startups, Tel Aviv parties and cherry tomatoes.

For too long the left has been telling these young people that everything here is awful — checkpoints, discrimination and the exclusion of women. For too long these intelligent, impressive and warm young Jews have not heard a strong Israeli voice talking with pride about the Israeli miracle while acknowledging that Israel does have some flaws.

Birthright has done wonders and lit a Jewish-Israeli spark in the hearts of hundreds of thousands in the past 15 years. But since Zionism has not provided a reliable, relevant and inspirational narrative to galvanize these millennials, many are simply keeping their distance. And when they arrive on campus and are exposed to anti-Israel venom, the Jewish and pro-Israel identity of many of them collapses.

There is no greater danger to Israel and the Jewish people than this collapse. Our fate will not only be determined on the country’s southern or northern borders, but on the quads of American campuses. To win the hearts and minds of young American Jews, we must define a revitalized, moral and liberal Zionism.

If there is still a Jewish national leadership in Jerusalem, New York or Los Angeles, it must wake up and take immediate action. As things stand now, the Jewish future is slipping through our fingers.