At Harvard, the Jewish student group Hillel was barred from co-sponsoring a discussion with a Palestinian student group. At Binghamton University, a Hillel student leader was forced to resign his position after showing a film about Palestinians and inviting the filmmaker’s brother to speak. And on many other campuses, Hillel chapters have been instructed to reject collaboration with left-leaning Jewish groups.

At American colleges, few values are as sacred as open debate and few issues as contested as the Israeli-Palestinian conflict. But Hillel, whose core mission is to keep the next generation of Jews in the fold, says that under its auspices one thing is not open to debate: Those who reject or repudiate Israel have no place.

This month, the students at the Swarthmore Hillel rebelled, declaring themselves the first “Open Hillel” in the nation. They will not abide by Hillel guidelines that prohibit chapters from collaborating with speakers or groups that “delegitimize” or “apply a double standard” to Israel.

The Hillel dispute has amplified an increasingly bitter intra-Jewish debate over what is permissible discussion and activism about Israel on college campuses.