On Sunday, hundreds of mostly young, American Jews rallied in Washington, D.C., during the first day of the American Israel Public Affairs Committee 2017 Convention, to protest the expansion of Israeli settlements in East Jerusalem and the West Bank.

“We’re protesting [AIPAC] en masse as Jews to say that to be Jewish in America at this moment doesn’t mean to support Israel unconditionally,” said 25-year-old Yonah Lieberman, one of the co-founders of the anti-settlement group IfNotNow, which spearheaded the protest in Washington D.C.

Lieberman described Sunday’s march as “the biggest ever Jewish-led protest of AIPAC.”

"Palestine, my friend, you do not walk alone, we will walk with you." AIPAC is not our establishment. #JewishResistence #ResistAIPAC pic.twitter.com/frl3U2JWkg — Abraham Gutman (@abgutman) March 26, 2017

Non-Jewish leaders like academic and activist Cornel West joined in Sunday’s protest, which saw participants briefly blocking the doors of the conference.

"A precious Jewish child in Tel Aviv has the same value as a precious Palestinian child in Gaza." - Dr. Cornel West at #ResistAIPAC pic.twitter.com/yGylxxmGzO — IfNotNow (@IfNotNowOrg) March 26, 2017

The annual conference of the powerful pro-Israel lobby draws heavyweights from both ends of the political spectrum: This year’s speakers include House Speaker Paul Ryan (R-Wis.) and House Democratic Leader Nancy Pelosi (D-Calif.). Though the group describes itself as bipartisan, it’s commonly viewed as a right-leaning organization ― or at least one that is unfriendly to criticism of the Israeli government’s right-wing policies.

AIPAC has historically avoided taking a firm stance on settlements, but has had a hand in influencing policy that tilts in their favor. Critics, like Lieberman, are more blunt in their assessment:

“AIPAC is the largest institution that supports Israeli settlements,” he said Sunday. “They’ve done more in the past 50 years to support occupation than anyone else in the Jewish community.”

Over 1000 protesters streaming out of #ResistAIPAC changing "If not now, when," through the Red Sea to our freedom. #JewishResistance pic.twitter.com/io4mMreH7j — IfNotNow (@IfNotNowOrg) March 26, 2017

Sunday’s protests are symbolic stands against not only Israel’s half century-long settlement stance, but policies of President Donald Trump’s nascent administration.

Earlier this year when the Israeli government approved the construction of thousands of new settlement homes in the West Bank and East Jerusalem, despite Palestinian opposition and widespread international condemnation, Trump’s administration took a more amiable stance on the development than those of previous administrations ― which flatly opposed any construction of settler homes.

The Trump administration’s closer alignment to the Israeli government was confirmed at AIPAC by Ron Dermer, Israel’s ambassador to the U.S., during Sunday’s conference.

“For the first time in many years, perhaps even many decades, there is no daylight between our two governments,” Dermer said.

AIPAC will be pro-Israel at any cost, prioritizing the occupation over the safety of the Jewish community and other marginalized people in America. Sara Sandmel, an IfNotNow member

AIPAC was also criticized for what protesters said was a weak stance against a growing wave of anti-Semitism in the U.S.

“I’ve never seen the sort of antisemitism we’re seeing today, but despite bomb threats and desecrated cemeteries, AIPAC has chosen to remain silent,” Sara Sandmel, an IfNotNow member from Boston, said in a statement Sunday.

“This proves without a doubt that AIPAC will be pro-Israel at any cost, prioritizing the occupation over the safety of the Jewish community and other marginalized people in America.”

Lieberman said the new dynamic creates a “unique moral moment for the Jewish-American community.”

“Now, we have a unique role to play to ensure the occupation comes to an end,” he said. “We have a responsibility to resist it.”