Correction: An earlier version of this article incorrectly said that Israel recently allowed building materials to enter Gaza for the first time in years. The materials were the first for the private sector in five years; Israel had previously allowed the entry of some construction materials for Israeli-approved projects carried out by international aid organizations. This version has been corrected.

Fatima still dreams about Ahmed. Sometimes they’re playing with toys as they used to do. But in other dreams, she’s looking over the edge of the balcony at her brother’s smashed and bloodied body, his pink brain spilling from his skull, her father screaming through his tears.

Ahmed was 7 when he was killed by an Israeli airstrike during the 2008 Israeli invasion of Gaza. Fatima was 8 at the time — but that was “old enough to remember,” said her father, Osama Mohamed Qurtan.

Four years later, Fatima has been through therapy. She has taken what her father calls “strong” medications to manage the flashbacks. Their new apartment is darker and more cramped than the old one, but the Qurtans needed to get away from the scene of the trauma, the doctors said.

Fatima’s listlessness and spontaneous aggression had started to improve, Qurtan said — until war struck again in November.

This time, the explosions felt just as personal as they did previously; the possibility of death just as likely. When Israeli airstrikes rattled the buildings for a week during the Jewish state’s latest confrontation with Hamas, the eight surviving Qurtan children hid in the stairwell, as Gaza schools have taught children here to do.

Gazans often talk about the inescapability of war and the symptoms of their suffering. They cast Gaza as a prison — both physical and psychological, where Israeli bombardment comes every so often and there is little to do but bear it.

Indeed, there are few places in the Arab world where psychology and trauma are as openly discussed as they are in Gaza. But health professionals here argue that there are few places in the region that contain a population so traumatized, a youth so obsessed with conflict.

Every day on his return home from school, Ahmed Qurtan’s cousin and best friend, Zohair, sees a banner bearing a portrait of himself, bloodied and bandaged. Hanging next to it, on a wall in the entryway to the family’s building, is a similar portrait of Ahmed in his funeral shroud.

Zohair used to be much smarter and more active before suffering a head injury in the same airstrike, his father, Alaa Mohamed Qurtan, said.

“He’s not normal now,” Qurtan said, as his son cast his long eyelashes shamefully at the floor.

Psychologists say that few in Gaza would qualify as “normal.” The cramped territory has operated under an Israeli-enforced blockade that has strictly limited the flow of goods and people since the militant group Hamas won an election here in 2006. The enclave’s 1.7 million people, half of whom are younger than 18, have endured two wars in four years. Nearly everyone in Gaza knows someone who has died a violent death.

It’s the long-term implications that worry some experts the most. “Gaza right now has all of the reasons there for people to go toward the extreme,” said Issam Younis, director of the Al-Mezan Center for Human Rights in Gaza City, who has documented the effect of war and blockade on Gaza’s population. “In putting a whole nation under siege, you obstruct their future. And then what do you expect?” he said. “More hatred, more enmity and more resistance against the Israelis.”

Isolated mind-set

Palestinian and Israeli intellectuals say that if Israeli society has grown more conservative and inward-looking in recent years, Gaza has mirrored it. And while the rhythm of war has taken its toll through trauma, the strip’s isolation has had its own effect on a generation’s mind-set.

Palestinian identity has long centered on resistance to an Israeli enemy, but Fatima’s parents’ generation still managed to engage with foes during the occupation and intifadas of the 1980s and ’90s, when Israeli troops roamed Gaza’s streets and many Palestinians crossed into Israel to work.

No one in Gaza wants a return to occupation. But the virtual absence of interaction between ­Gazans and Israelis in recent years and the growing distance with which Israel wages war — through unmanned surveillance drones and warplanes — have left the younger generation with a different perspective.

“In engaging with the other, you rediscover yourself,” said Younis, adding that he and his peers have some Israeli friends. “We still speak Hebrew,” he said.

“But those young guys, they’re ­a little bit different from their parents. And the Israelis created them that way,” Younis said. “Those guys — the people under 20 — their only engagement with the Israelis is through the Apache and the F-16.”

The experience of repeated conflict with an increasingly foreign enemy has left Gaza’s youths on edge, health professionals say. Anxiety, excessive worrying, depression and post-traumatic stress disorder are rampant among Gaza’s young people.

Teachers, parents and psychologists talk of children who act out in the classroom, struggle with speech impediments and concentration, jump at loud noises, and wet their beds at night.

Salah Haj Yehia, director of mobile clinics in the strip for the Israeli nongovernmental organization Physicians for Human Rights, said he participated in a psychological health initiative in recent years that showcased the drawings of Gazan children. The exercise was disturbing, he said.

“You saw drawings of air raids, tanks firing, homes being torn down,” he said. “This is what is on the minds and in the imaginations of Gazan children. It’s not a happy life that you see in those drawings.”

More than a month after Egyptian-brokered cease-fire negotiations between Israel and Hamas, some Gazans are hopeful that the days of isolation are coming to a close. Hamas demanded an end to Israel’s blockade as one of its terms for maintaining the cease-fire. And last Sunday, Israel allowed a cargo of building materials for the private sector to enter Gaza for the first time in years.

Many still believe that war remains inevitable, and that any recent gains against the Israeli blockade came as the result of improved rocket power.

An enemy they haven’t met

To children like Fatima, who have never seen an Israeli, the people who bombed the strip’s dense urban neighborhoods in 2008-09 and again in November remain distant, almost mythological villains.

At the Muatassim B’illah school in Gaza City, where murals along the courtyard depict teddy bears, a Koran, a gun and a map of Palestine, children tell frightening stories from the November war with Israel, but none has ever met an Israeli.

Gaza was attacked, they say, for the same reason Israel struck in 2008 — to kill Palestinians and seize more Palestinian land. (Israel says its warplanes carry out precision strikes on carefully identified terrorist targets.)

“At the mosque, the sheikhs always tell us we have to be fighters when we grow up to retrieve our land,” said Mahmoud Shukri, a 12-year-old.

On a recent evening, when a routine electricity outage left the Qurtan family apartment shrouded in darkness, Fatima echoed a similar sentiment.

“I want to be a policewoman when I grow up,” she said, dressed in a pink sweater as her younger siblings tackled each other to the concrete floor. “I want to take back the rights of the innocent children, and I want to take revenge for my brother’s life.”

Ramzy Hassouna in Gaza City and Ingy Hassieb in Cairo contributed to this report.