Tens of thousands of displaced Gazans struggle to find food, water and shelter.

In Lod, which lies just south of Tel Aviv, Jews and Arabs often live in the same building, she said, but now Arabs are reluctant to go into the air-raid shelters. “They say they see hate in the eyes of the Jews,” Ms. Shehada said. “They say they see hate, but I think what they really see is distress and fear.”

Arab citizens of Israel, many of whom want to be identified as Palestinians, make up some 18 percent of the population. They have been caught for years between their loyalty to the state and their desire for an end to the Israeli occupation of Palestinian lands, the creation of an independent Palestine and a better life for themselves.

Now, after this unprecedented killing of Israelis inside Israel, when an enraged Israeli Jewish population is calling for revenge, normal tensions have been raised to almost unbearable levels.

The leading Arab politicians in Israel, like Mansour Abbas and Ayman Odeh, both members of the Knesset, have clearly condemned the actions of Hamas, the Palestinian faction that carried out the attack on Israel, and called for calm.

But people are torn in their feelings, Ms. Shehada said, and so they tend to hide them. Young Arabs at first felt pride in the resistance of Hamas, which controls the Gaza Strip, she said. “In the first moment when the people of Gaza invaded Israel, people were happy, they felt that someone was doing something about the situation.”

But that surge of pride faded quickly, she said. “This was before we saw all the images of slaughter, kidnap and rape,” Ms. Shehada said. “This is not a legitimate form of struggle.”

In May 2021, during another Israeli-Palestinian crisis, Lod was wracked by riots and mutual hatred between Jewish and Muslim communities. Ms. Shehada, 40, says she was attacked in her own home by Jews throwing rocks.

Even in more normal times, Lod has deep-seated problems of poverty and crime, with Arab criminal organizations operating with little interference from the Israeli police, people here say. Even the local government is largely segregated, with separate Arab and Jewish sections within departments.

The police are the responsibility of Itamar Ben-Gvir, the national security minister and leader of the ultranationalist Jewish Power party, a member of Prime Minister Benjamin Netanyahu’s right-wing coalition government. Mr. Ben-Gvir, who has supported settler violence against Palestinians in the occupied West Bank, has also been ramping up tensions with Israel’s Arab population.

He has talked of “storming” the Aqsa Mosque compound, one of the Muslim world’s holiest sites, and in late July, he led more than 1,000 ultranationalist settlers to the site, infuriating Muslims and prompting Hamas to say that it is fighting to defend Al Aqsa.

Mr. Ben-Gvir has spoken this week of renewed Arab-Israeli violence in cities like Lod and ordered the police to prepare for riots, which Ms. Shehada and others view as a dangerous provocation.

Mohammad Magadli, one of Israel’s most prominent Arab journalists, is more optimistic. He sees the shock of the past week bringing a sort of stunned calm. Unlike in 2021, he said, in mixed cities, “the Arab and Jewish societies are more aware of each other’s pain and can understand how destructive the consequences can be if they don’t consider each other’s feelings.”

“There is greater responsibility between the two societies,” Mr. Magadli said, “even among the leaders who, from the outset, called for calming the situation.”

Ms. Shehada said her aunt was visiting Gaza now and could not leave. Buildings on either side of where she is staying have already been bombed, Ms. Shehada said, then paused, sighed, and said, “I don’t think they will survive this war.”

In Ramla, a similarly mixed town nearby, the sprawling market normally overflowing with local vegetables and fruits was nearly empty, with an unusual wariness in the air, said Mousa Mousa, 23, an Israeli Arab in a Hebrew-language T-shirt advertising his juice stall. “I’m not sleeping,” he said. “I’m afraid of the reaction of the villagers on the road to what Hamas did.”

The market is a mix of Arabs and Jews, he said, “but the feeling is different now.”

“I feel an animosity from the people here — they’re not smiling as they used to,” Mr. Mousa said. “I try to keep my head high.”

He said he had contempt for the politicians who stoked hatred inside each community. “They thrive on division,” Mr. Mousa said bitterly. “That’s what politics are based on.”

What Hamas did has changed life here profoundly, he said. “I don’t think there’s a way back,” he added. “People will not be as they were.”

In East Jerusalem, too, near the uncharacteristically empty Old City, there is a palpable tension and a more visible presence of Israeli police.

In normal times, they tend to stop and check young Arab men every so often. But Adham, 19, says that now he is being stopped three times as he makes the short walk from his father’s shop near the Damascus Gate to their home in the Old City. Each time, he is asked to show his ID card, lift his shirt and drop his trousers. His father asked that their last name be withheld for fear of their security in the current environment.

Adham said that he admired Hamas’s boldness. “Yes, they represent the Palestinians,” he said. “They are the only ones who protect the Palestinians.”

Like many young men here, he has little respect for Mahmoud Abbas, the president of the Palestinian Authority. “In our eyes, he is a traitor” for cooperating with Israel, Adham said, especially on security in the occupied West Bank.

Unlike Arabs in Ramla or Lod, who are part of Israeli society, most Palestinians in East Jerusalem are not Israeli citizens and feel less torn between loyalties. In 1967, when Israel annexed East Jerusalem, it made the Palestinians there legal residents, but not citizens.

Mahmoud Muna runs one of Jerusalem’s finest bookshops, catering to everyone. He identifies as a Palestinian from Jerusalem and favors a unitary state based on democracy and equal rights. He sees people like himself as potential models for a different kind of integrated state.

But now, he said, there is an unusually high level of “tension, anxiety, anger, confusion and fear that has grown among Palestinians, and I feel it myself.”

The police presence has been increased in and around East Jerusalem, and Mr. Muna himself has been stopped twice for checks in the past five days, always moments that can produce friction. “Being past 40 helps you keep your cool,” he said.

Are Palestinians in Israel in a bind? He paused, then said, “We are always in between.”

Friends who go to work in West Jerusalem tell him that “everyone is stressed and angry, but everyone is pretending or putting on a face.” People say banalities like “it’s crazy” or “it’s difficult” or “I can’t understand it,” Mr. Muna said, adding, “This is so you don’t have to say your opinion, but to say nothing is also not acceptable.”

Moments like this one are clarifying, too, he said: “It is a good time to see things we don’t normally see,” like the absence of acquaintances who have been called up as reservists to the army.

“Palestinians are reminded to what extent Israeli society is militarized,” he said. “Those you were eating with yesterday are now at the front, and what are they doing now?”

This week has encapsulated the entire conflict, Mr. Muna said. “The high level of nationalism, of we and them, cannot be higher than now,” he said. “Resistance becomes terrorism and vice versa, and us and them, and civilians and army — all these terms are in sudden contrast.” One side speaks of a new Holocaust and the other of a new Nakba, or catastrophe, which is what Palestinians call their mass displacement and dispossession during the 1948 Arab-Israeli war.

“That’s the graveness of the moment,” Mr. Muna said, “like shrinking the whole last 100 years into a week.”

Natan Odenheimer contributed reporting.