A campaign official working for Sen. Bernie Sanders (I., Vt.) apologized Tuesday for suggesting Jewish Americans and the U.S. government may have "dual allegiance."

Belén Sisa is Sanders's national deputy press secretary on his 2020 presidential campaign. In a Facebook post last month, Sisa shared an article likening the relationship between Democrats and the American Israel Public Affairs Committee (AIPAC) to that between Republicans and the National Rifle Association (NRA). Sisa was defending comments from Rep. Ilhan Omar (D., Minn.) about the Jewish community. Sanders has defended the same comments, refusing to condemn Omar.

When a Jewish friend of Sisa's worried about the murderous history of suggestions that Jews are less than loyal to their country of residence, Sisa responded by defending the accusation.

"This is a serious question: do you not think that the American government and American Jewish community has a dual allegiance to the state of Israel?" Sisa wrote in a now-deleted comment.

When another commenter asked whether the question applied to her boss, Sisa replied: "I think I would probably have to ask him? But his comments make me believe other wise as he has been very blunt on where he stands."

Rep. Lois Frankel (D., Fla.) condemned Sisa's remarks. "I would totally disagree with that. It’s ridiculous," she told Politico. "That’s just a terrible statement to make."

The accusation that Jewish Americans are loyal to Israel as opposed to their country of citizenship is a classic anti-Semitic canard. A 2018 publication from the Begin-Sadat Center for Strategic Studies explains that, "[i]n its most extreme form, the charge of dual loyalty amounts to an accusation of treason."

Sisa was responding to comments Omar made during a February town hall in Washington, D.C. The freshman congresswoman made fresh anti-Semitic comments while taking on criticism for her past accusations. She claimed the pro-Israel community demanded politicians be loyal to Israel in addition to the United States. The charge repeats an enduring anti-Semitic accusation that has been the impetus for anti-Jewish recriminations for centuries.

"I want to talk about the political influence in this country that says it is okay for people to push for allegiance to a foreign country," she said. The comment provoked condemnation from members of both parties, and a watered-down resolution condemning the remarks.

Sisa, asking about dual loyalty on Facebook, tried to limit the debate to Omar's comments, to the exclusion of thousands of years of anti-Jewish accusations. "I’m asking not to rule out the history of this issue, but in the context in which this was said by Ilhan," she wrote.

She has since apologized to Politico for the comments. "I used some language that I see now was insensitive," she said. "Issues of allegiance and loyalty to one's country come with painful history."

The comments extend a month of Democrat turmoil over anti-Semitism in the party. After Rep. Nita Lowey (D., N.Y.) tweeted, "Omar continues to mischaracterize support for Israel," Omar responded that members of Congress should not be "expected to have allegiance/pledge support to a foreign country" in order to serve or sit on the House Foreign Affairs Committee.

In response to Omar's comments, Rep. Ted Deutch (D., Fla.) addressed the dual-loyalty charge in a floor speech last week. "It's worthy of being singularly called out. Jews control the world? Jews care only about money? Jews have dual loyalty and can't be patriotic members of the country which they live? Words matter," he said.

Deutch, who is Jewish, was upset Democrats would be slow to take the threat seriously. "Jewish elected officials are saying that this history that we know well is invoked by referencing dual loyalty, some of my colleagues are saying it doesn't matter what that history means to me," he said.

Omar, a member of the Progressive Caucus, has drawn scrutiny and condemnation since taking office in January for a series of anti-Semitic remarks. In another tweet responding to the early February controversy, Omar claimed the strong reactions to her tweets, which she herself called anti-Semitic, were really "smears" against her.

The Minnesota Democrat supports the anti-Israel Boycott, Divestment, and Sanctions (BDS) movement, though during her campaign she spoke in a synagogue and claimed to oppose it. Sisa likewise expressed "solidarity" with "Palestine" during clashes between Palestinians and Israeli forces.

Clashes included Palestinians efforts to infiltrate from Gaza into Israel. Per the Washington Post article Sisa shared in her Facebook post:

[T]he protests appeared to have a more violent edge than in previous weeks. Some young men brought knives and fence cutters. At a gathering point east of Gaza City, organizers urged protesters over loudspeakers to burst through the fence, telling them Israeli soldiers were fleeing their positions, even as they were reinforcing them.

Sisa's parents visited the United States from Argentina when she was 6 years old and overstayed their visas. She is an Argentine citizen working on a U.S. campaign.

Sanders has a history of hiring fervently anti-Israel and anti-Semitic staff. Two of his top staffers, Matt Duss and Faiz Shakir, "were chastised several years ago for their involvement in an anti-Semitism scandal that gripped a prominent Washington, D.C., think-tank." Simone Zimmerman, the Jewish outreach director for Sanders in 2016, supports BDS.