For Jews around the world, the aftermath of Oct. 7 has been a time not of just horror, grief and mobilization, but also of bewildering revelation. Suddenly, many Jews feel that long-held beliefs must now be challenged, modified and even rejected.

For Israelis, the revelations are glaring and gut-wrenching. For such a catastrophe to take place, so many critical systems had to fail, so many assumptions had to be wrong — from the political and strategic level to intelligence to budgeting and military preparedness. To put it bluntly, Israelis’ faith in the whole security system that has kept them alive and at relative peace for decades has been shaken to its core — just when they must rely on that system to carry them through a bitter war. It’s awful.

There are also positive revelations. The judicial reform and protests of the past year had led many Israelis to start asking whether the country even had a future. In the last three weeks, however, Israelis have come together with a strength and focus far beyond what anyone thought possible. When a true crisis came, politics fell away and the nation united.

For diaspora Jews, the revelations have been no less profound. Liberal Jews, who make up the clear Jewish majority in the U.S., have long worried that the progressive alliance was being undermined by rising left-wing antisemitism and Israel hatred.

But nobody understood the extent and depth of that hostility until the time came to denounce the actual butchery of Jews, the maiming, torturing, raping, beheading, kidnapping and burning alive of people — from children to the elderly.

Instead of condemnation, there was justification and, in some corners, even celebration.

Few understood the inhumanity of so many of their progressive “allies.” Few realized how true was the claim that anti-Zionism really was nothing more than a veil for the most vicious forms of antisemitism.

The long-held belief that right-wing antisemitism is a far greater threat than left-wing antisemitism is no longer tenable.

But the flip side of this is that everyone seems to understand now the profound imperative of Jewish unity. We shouldn’t ignore our differences but must recognize that we are all in the same boat — and that boat is quickly taking on water.

What comes next?

With revelation comes rethinking. The deepest questions must be asked: Who are we? Who are our true friends? What can we rely on? What does our tradition teach us that can help? What is our strategy for survival now? Where are the institutions that were supposed to protect us? And most importantly: What are the changes we need across the length and breadth of Jewish life moving forward?

This will require hard conversations across our world, not just within our limited circles of denominations, movements and organizations, but between them as well. A seismic shift in reality requires a tectonic rethinking — of our affiliations, institutions and approach to education, Zionism, philanthropy, community, religion and the U.S.-Israel relationship. It cuts across all parts of Jewish life, from politics and policy to rituals and religion, from activism and community programming to schools and books.

Nothing should be taken for granted. Not anymore.

This great Jewish rethinking will be hard, especially now. So many of us have been directly affected by the war. We are a traumatized people,  far more than we may be aware. It feels almost indecent to make positive, ambitious, optimistic plans for the Jewish future. But we know it must be done. Urgently.

Like all Israelis, I am still hurting, still processing, still angry. I don’t know if I will ever get over it, and most of the time I don’t even want to.

But when I take a minute to breathe, to step away from the magnitude of our tragedy and the fears for the future of my family, my country, and my fellow Jews around the world, for just a brief moment, I allow myself some hope as well.

I know we can and will build a better Jewish world.

David Hazony will speak at 6:15 p.m. Nov. 3  on the topic “Is Zionism Relevant Today?” at Congregation Beth Am in Los Altos Hills. This piece is presented in partnership with the Z3 Conference on Nov. 5 in Palo Alto. The views expressed in this article are the author’s own and do not necessarily reflect those of J.