Naftali Bennett made his name as a hard-right Israeli ultranationalist demanding more Jewish settlement in the occupied West Bank and harsher action against Palestinian militants.

Now he is on the verge of claiming Israel’s highest office with the support of the fringe-left and the Jewish state’s only Islamist Arab party.

As the 49-year-old prepares to ascend to the job — dethroning Benjamin Netanyahu, his one-time mentor and five-time prime minister — his incendiary comments are being parsed for hints for what sort of leader he will be.

To those who have risen alongside him, and friends who have known him for decades, the ability to inhabit different roles — hard-right standard-bearer, tech multi-millionaire and, suddenly, a uniting voice in a divided country — says more about Bennett than the incendiary comments that have made headlines in his calculated rise to the summit of Israeli politics.

“He’s always had a very considered public persona. Not calculated, but carefully calibrated,” said one of two longtime friends who asked for anonymity to talk freely about the likely next leader of the Jewish state. “They add up to very convenient contradictions,” said the second. “Naftali the politician is always evolving.”

That evolution will continue on Sunday, when 61 members of Israel’s 120-seat parliament are expected to vote Bennett into his first premiership, ending Netanyahu’s 12 years in office.

It would usher in several firsts for the Jewish state: the first kipa-wearing, Sabbath-observing religious Jew to run the country; the first to share power with an Arab party, the Islamist Ra’am; and the first prime minister who controls just six Knesset seats.

This would catapult a man who has lived in the shadow of Netanyahu — first as chief of staff, then as a rightwing anchor in successive coalitions — to his political executioner, sending Israel’s longest-serving premier to the opposition benches just as his corruption trial gathers momentum.

Bennett, leader of the small Yamina party, would replace him at the helm of an eight-headed coalition that spans from the fringe left to the ultranationalist right. He would take the top job for two years as part of a rotating premiership with Yair Lapid, the opposition leader who assembled the coalition.

Keeping it together would force Bennett to evolve further, said Yohanan Plesner, president of the Israel Democracy Institute, who has known him since their time in the Sayeret Matkal, the elite unit of the Israeli Defence Force.

Then, the Sayeret Matkal usually recruited from among Israel’s Ashkenazi Jews, descendants of the secular Europeans who founded the state. But Bennett hailed from a different group that identifies as the national religious camp, which blends Orthodox Judaism with state-building. The camp, which generally believes in expanding settlement in the occupied West Bank, has been gaining prominence in Israel since the late 1990s.

“Bennett was one of the first to mark the ambition of members of this national religious sector to join one of the leading elite institutions that make the country,” Plesner said.

He continued: “The fact that he’s going to be the first prime minister from this sector is a continuation of that same line of thought — that the national religious camp is now the main dish, not just a supplement, and they are taking on broader responsibilities.”

Born in Israel to American Jewish parents, his successful post-military business career culminated in the multimillion-dollar exit from a tech company. The military record that is key to his persona revolves around demanding that the Israeli government free up the armed forces to take harsher steps against Palestinian militants such as Hamas.

But his time in the military was overshadowed by the Qana massacre of 1996. Leading a unit deep into Lebanon during Operation Grapes of Wrath, he called in an artillery strike near a UN shelter after they came under fire from Hizbollah. At least 100 civilians were killed.

Decades later, he was forced to deny leaked comments from a cabinet meeting that he “had killed lots of Arabs — and there is no problem with that”.

For the international community, which must deal with an Israeli premier who has already outlined his rejection of a Palestinian state, his short stint in 2010 as leader of an umbrella group of West Bank settlers is of equal concern.

“There are a lot of low-hanging fruits in the settlement enterprise that he can pluck off very quickly to appease that base,” said a European diplomat, who has met Bennett to discuss the demolition of Palestinian-built and EU-supported West Bank villages. “It’s good television: send in soldiers to rip down tents and homes, then change the channel.”

But Oded Revivi, mayor of the Efrat settlements and foreign envoy for the group, remembers Bennett’s stint as uneventful and ineffective.

“I can’t say that during this period there was a single specific goal that was completed,” he said in an interview. And Bennett heading a coalition that included the left and an Arab party would lead to “a standstill”, Revivi predicted.

“They won’t be able to promote a two-state solution, nor will they be able to evacuate any of the settlements,” he said.

The compromises forced by the nature of the coalition would also temper Bennett’s hard-right urges, said analysts and the friends of Bennett.

After two years of political paralysis, passing a budget, agreeing stimulus spending while keeping public debt — which has soared above 70 per cent of gross domestic product — under control are expected to be the first orders of business, they say. The coalition has already informally agreed to focus on the economy and recovering from the pandemic.

“Just by passing a budget, making competent civil service nominations across the board, getting the machinery of government to work again and pass legislation, it will automatically introduce a fresh new start and atmosphere,” Plesner said.

“He doesn’t need to solve the 100-year conflict with the Palestinians to be perceived as a competent and successful prime minister.”