The day Israelis woke to the horror that the Palestinian squads that had infiltrated their country were shooting soldiers and civilians and dragging captives back to Gaza, the shadowy commander of Hamas’s military wing released a rare message blessing the attack.
Speaking from a secret location, the commander, Muhammad Deif, described the operation as an explosion of anger at Israel’s treatment of Palestinians and told his forces it was a first step toward Israel’s destruction.
“Righteous fighters, this is your day to bury this criminal enemy. Its time has finished. Kill them wherever you find them,” he said in an audio message posted on social media. “Remove this filth from your land and your sacred places. Fight and the angels fight with you.”
Mounting grievances fueled Hamas’s decision to attack, but the nature of that attack was shaped by a deep thirst for revenge built up over decades of conflict — a desire to see Israel bleed.
Hamas acted on that desire on Saturday, shocking the world by bringing the fight inside Israeli communities and shattering the sense that Israel could keep its conflict with the Palestinians elsewhere.
“What Hamas is doing is trying to flip the table back on the Israelis, saying you can’t forget about the Palestinian issue and we can undermine the myth of your invincibility,” said Tareq Baconi, the author of a book about Hamas in Gaza. “That in itself is a huge transformation in the Palestinian imagination, and I don’t think we can see or understand the implications of it yet.”
The conflict between Israel and Hamas has regularly erupted into bouts of tremendous violence in Gaza for more than a decade, but the scale of Hamas’s attack, and its taking of about 150 Israeli captives, has significantly raised the stakes on both sides.
Prime Minister Benjamin Netanyahu of Israel has vowed to destroy the group, and Israeli forces are massing at the Gaza border for a potential ground invasion. Hamas leaders have vowed to keep fighting and called other anti-Israel forces to join in, raising the specter of a regional war.
Most likely to pay the highest price in Gaza are civilians, who are among the hundreds who have already been killed in Israeli airstrikes since Saturday. If Hamas’s leaders considered the cost to Gaza’s civilians of such an attack, it clearly did not impede their decision to proceed.
“It speaks to the fact that these kinds of groups or movements have political objectives that they pursue and the human cost will be a secondary consideration to that,” said Dana El Kurd, an assistant professor of political science at the University of Richmond.
Deciphering Hamas’s motives requires understanding how the group sees itself in Palestinian history. Hamas was founded in the late 1980s during the first Palestinian Intifada, or uprising, against Israel as an Islamist group dedicated to destroying Israel and replacing it with an Islamic state.
While its leaders have more recently allowed for the possibility of a two-state solution, the theoretical endgame of decades of Mideast peace efforts, it has never sought negotiations with Israel, unlike other Palestinian factions.
Instead, it considers Israel’s existence illegitimate, describing the Jewish state as a colonial project and itself as an anticolonial movement.
Hamas drew widespread international condemnation during the second Palestinian uprising that began in 2000 for deploying suicide bombers to civilian areas. Israel, the United States and many other countries consider it a terrorist organization.
Since 2007, Hamas has been the de facto ruler of the Gaza Strip, and Israel has imposed a strict blockade on the territory, often in tandem with Egypt.
The group’s top political official, Ismail Haniyeh, is based in Qatar. Other senior officials reside in Beirut, where they keep close ties with Hezbollah, the Lebanese militant group that is also committed to Israel’s destruction.
To avoid assassination by Israel, Hamas’s leaders in Gaza rarely appear in public and are believed to move around the territory in tunnels that connect underground bunkers. Many have their own bad blood with the Jewish state.
The Hamas leader in Gaza, Yahya Sinwar, spent two decades in prison for killing Israeli soldiers. He was released in 2011 in a prisoner exchange and returned to Gaza.
Mr. Deif, the head of Hamas’s military wing, has not been seen publicly in years. Israel has tried to assassinate him repeatedly, possibly maiming him or blinding him in one eye. Israel bombed his home in 2014, killing his wife and infant son.
Hamas’s commitment to armed struggle distinguishes it from the Palestinian Authority, which was established during the peace process as a sort of Palestinian government in waiting and now has limited control over parts of the West Bank.
Hamas officials argue that the peace process has failed the Palestinians, leaving armed struggle, or resistance, as the only option.
In recent months, Hamas had faced rising discontent with its failure to improve living conditions in Gaza, where most residents are stuck, poverty is rife and power cuts are common.
Saturday’s attack most likely sought to draw attention away from that while bolstering Hamas’s resistance credentials among Palestinians.
“The Palestinian Authority has completely abandoned the idea of representing Palestinians in any kind of resistance, nonviolent or violent, so now Hamas has claimed that mantle,” said Ms. El Kurd. With such a bold attack, Ms. El Kurd added, Hamas sought to prove to Palestinians that it is “the bulwark of resistance.”
Many Gazans do not embrace all of Hamas’s ideology, but there is broad support for its fight against Israel. Most of Gaza’s two million residents are refugees who were or are descended from Palestinians who fled or were expelled from what is now Israel during the war surrounding its creation in 1948.
Some Gazans trace their roots to villages that once stood where Saturday’s incursion took place.
In the days since the attack, Hamas leaders have lauded the assault as a success and vowed to kill Israeli captives if Israel bombs civilians in Gaza without warning. But they have otherwise made few specific demands, suggesting that more war is to come.
Israel has repeatedly bombed Gaza over the years, killing large numbers of Hamas members and civilians but without significantly degrading the group.
Mr. Baconi, the author, dismissed the idea that the Israeli military could destroy Hamas because many Palestinians will continue to support its anti-Israel struggle.
“This isn’t just an organization,” he said. “It is also an ideology, and that ideology isn’t going to go anywhere.”
Health officials in Gaza said on Wednesday that over 1,100 Palestinians had been killed and many more wounded since Saturday. The breakdown between fighters and civilians was not clear. That toll will most likely rise significantly as Israel bombs the territory and possibly begins a ground invasion.
It remains unclear whether the high cost to civilians will blow back on Hamas. Even when Hamas attacks first, Gazans tend to blame Israel for their misery, and many have been through so many wars that fatalism prevails.
“From what I hear from Gazans, it is a very repetitive war,” said Imad Alsoos, a researcher from Gaza at the Max Planck Institute for Social Anthropology in Germany. The refrain he said he hears from friends and family is, “We have nothing to lose.”
The other common refrain in Gaza is Hamas declaring that it has won.
“Every war, no matter how many Palestinians die, Hamas will come after it and say, ‘We are victorious,’” he said.
Iyad Abuheweila and Nada Hussein contributed reporting from Cairo.