Members of a storied food co-operative in Brooklyn have voted to boycott about a dozen products from Israel and Israeli settlements in occupied Palestine – capping years of contentious debate over a conflict half a world away that has threatened to rip apart a landmark institution for liberal New Yorkers.

The Park Slope Food Coop vote, which took place Tuesday night during a three-hour virtual meeting attended by about 7,000 of the co-operative’s 17,000 members, follows months of dueling campaigning that one local rabbi opposed to the boycott described as a “proxy war”. The boycott is supposed to impact some brands of tahini, peppers and persimmons as well as other products. Sixty-seven percent of participants voted in favor of the boycott.

What may seem like a trivial squabble of little significance beyond the largely privileged community the co-op serves has become yet another microcosm of the deep rifts over Israel that the war in Gaza has exacerbated.

The pro-boycott faction – led by Park Slope Food Coop Members in Solidarity with Palestine, and endorsed by more than two dozen advocacy groups including several Jewish ones – argued that the boycott is in line with the co-op’s long history of socially conscious shopping, and cited past boycotts of products from apartheid South Africa, and Chile under the Augusto Pinochet regime, as well as of several companies over their anti-labor or environmental practices.

“Our co-op has a long and proud tradition of more than 20 boycotts,” said Alyce Barr, a member for nearly five decades and one of the boycott proposal’s sponsors. “We want to build on this tradition by boycotting Israeli products until Israel complies with international law.”

The debate has drawn attention well beyond the co-op, which was founded in 1973 and has been the subject of numerous satirical portrayals over its stringent membership requirements and perceived self-importance. Dan Goldman and Brad Lander, two Democrats locked in a congressional primacy race in which Israel is also playing a central role, have both weighed in against the vote (although Lander made clear he was not telling people how to vote). Others, like Palestinian advocate and Brooklyn resident Mahmoud Khalil, have defended the boycott movement as the minimum response to Israel “slaughtering civilians and committing human rights violations daily”.

Tensions over two proposed ballots initiatives – one in favor of the boycott of Israeli products and one eliminating a requirement for a 75% supermajority for a boycott to pass – have played out for weeks (the second initiative also passed by a large majority). At times, those tensions have flared into confrontations that the co-op’s management condemned as antithetical to the organization’s spirit.

Pro-boycott advocates described being verbally abused by some anti-boycott members and passersby, including with a “homophobic and misogynist slur”, and having their table flipped over and materials dumped in the street by a co-op member.

In an email to members shared with the Guardian, the co-op’s leadership denounced what it called antisemitic and anti-Arab comments made during last month’s general assembly. In one statement cited by the email, a member reported: “We can’t keep making the same mistakes between we did with the Nazis and what we did with other hateful, racist groups. Jewish supremacism is a problem in this country.” Another comment reportedly cited the phrase “Arab supremacy” in connection with the events of 7 October 2023 and the Muslim Brotherhood.

“The co-op has always been a place for open discussion, including difficult and strongly held views across deep divides, but that discussion must remain grounded in civil discourse,” wrote Joe Szladek, the co-op’s general manager.

Co-op leadership has increased security measures, citing a series of incidents including “threatening letters, suspicious substances sent through the mail, aggressive phone calls and emails, repeated phone disruptions, hostile social media and online activity directed at staff and members”, Szladek said in the email. “These measures are not being taken in response to any one viewpoint or group of members.”