When Netanyahu returned as Israel's prime minister in 2009, he faced a major change in the region: the election of the radical Islamic group Hamas as the ruling party in the Gaza Strip three years earlier.

Since then, Netanyahu has been Israel's prime minister for almost all of his life.

From the beginning, Hamas has vowed to destroy Israel, and during the 2009 election campaign, Netanyahu vowed to destroy Hamas as well. What followed, however, was nearly 15 years of uneasy coexistence between the two. In the interim, successive Netanyahu governments and Hamas leaders have found each other useful for their respective purposes.

This strange symbiosis has lasted through years of escalation and reconciliation, periods of calm hope and chaos, until now. Now both Hamas and Netanyahu face the possibility of stepping down.

Hamas leaders were bombed and hunted down by the Israeli military after directing the Oct. 7 attack that killed at least 1,200 Israelis. The Israeli military has promised that Hamas will never rule Gaza again. Israel's devastating assault on Gaza has killed more than 11,000 people, according to Palestinian officials.

Netanyahu agreed last month to share emergency war powers with his main political rival, but has faced unprecedented public anger over his failure to prevent the October attack and the government's chaotic response after it. Opinion polls show that 75 percent of Israelis want him to resign now or be replaced after the war.

Adam Raz, an Israeli historian who has studied the relationship between Netanyahu and Hamas, said: "It was a strange alliance that has now come to an end. Hamas will no longer be the government of Gaza. I think we can also assume that Netanyahu's political career is coming to an end."

The situation is changing rapidly, and the fate of both sides is uncertain. Israel and Hamas agreed to a four-day cease-fire starting November 25. As part of the deal, 50 Israeli hostages will be released. Netanyahu vowed to continue fighting after the cease-fire with the goal of "eradicating Hamas."

Raz and other observers made it clear that Netanyahu did not anticipate the Hamas attack on Oct. 7, the deadliest day for Jews since the Holocaust.

But since Mr. Netanyahu returned to power, they said, he has instead largely pursued a strategy that does not undermine the status quo of a divided Palestinian population, allowing Hamas to rule Gaza and the rival Palestinian Authority to rule the West Bank.

Analysts say the division weakens the Palestinians' ability to oppose the Israeli occupation, thus achieving the goals of Netanyahu and opponents of a negotiated solution to the two-state conflict.

"In the absence of a unified leadership, Netanyahu can say that he cannot move forward with peace talks," said Dahlia Scheindlin, an Israeli pollster and political analyst. "It allows him to say, 'There is no one to talk to.'" '"

This situation has allowed Netanyahu to largely shelve the "Palestinian question," which has shaped the tenure of Israeli leaders for the past 40 years. Netanyahu's biographer, Anshel Pfeffer, said the prime minister was instead focused on Iran and other threats and Israel's development as an economic powerhouse.

"Netanyahu has always believed that the Palestinian conflict is a distraction that is used to create divisions in Israel," Pfeffer said. He called it the rabbit hole."

Year after year, successive Netanyahu cabinets have approved initiatives that have had the effect of easing the pressure on Hamas: Israel has agreed to regular prisoner releases, transfer funds from Qatar to pay public salaries in Gaza and improve infrastructure. Critics say Israel also funds Hamas' military operations.

Netanyahu wants to prevent any rapprochement between Hamas and the Palestinian Authority, even if the two sides come close in 2018.

"For the past 10 years, Netanyahu has worked hard to prevent any attempt to destroy Hamas in Gaza," Raz said.

Mr. Netanyahu's office declined to respond publicly. But a senior administration official, speaking on condition of anonymity, denied that Mr. Netanyahu had pursued a policy of keeping Hamas in power.

"He's the most cited prime minister in history, and I don't think you'll find anything in his speech that lobbies to strengthen Hamas," the official said. "The truth is quite the opposite. He has hit Hamas harder than any prime minister in history. He led three major military operations against Hamas in 2012, 2014 and 2021."

"He did not destroy Hamas, which is what his war cabinet instructed [the IDF] to do after the October 7 atrocity," the official said. That's what the IDF is doing right now."