JERUSALEM — In a trio of new polls, Israelis have declared what they think of the bribery case against Prime Minister Benjamin Netanyahu, and the answer is roughly the same as what they think of Mr. Netanyahu himself: About half think he should step aside. His right-wing supporters overwhelmingly think he should stay.

Mr. Netanyahu’s Israel is as polarized as it has been in generations, and under his lengthy tenure, the national conversation has become steadily more toxic. Now, as the prime minister awaits a possible criminal indictment, his efforts to cling to power could pose even greater strains on a society that already seems at risk of tearing itself apart.

“Imagine if, in the next few weeks, there is a justified case for Israel to go to war,” said Shlomo Avineri, a professor emeritus of political science at the Hebrew University of Jerusalem. “Half of this country would think Netanyahu’s position was impacted by his legal situation. That is unacceptable. Political decisions are sometimes existential in Israel. If we had to go to war, the decision would be contaminated for a lot of people.”

Mr. Netanyahu has dismissed the police recommendations to charge him as “slanted” and “full of holes, like Swiss cheese.” The attorney general, Avichai Mandelblit, praised the police on Thursday, in his first public remarks on the recommendations. The state prosecutors and the police, he said, had worked with the goal of “preserving the rule of law in Israel, turning over every stone in order to bring the truth to light.”

The next several months, as the nation awaits Mr. Mandelblit’s decision on an indictment, are likely to be raucous, with zero-sum politics taken to a new level. Mr. Netanyahu’s foes will portray him as a felon-in-all-but-fact, while his allies paint him as the persecuted victim of a left-wing conspiracy that extends all the way up to the commissioner of police.

But it has been all politics, all the time, in Israel for years.

Israel has always been a noisily contentious land of debates with the volume on 11. Beyond the left-right divide lies an unruly and acrimonious diversity, with fault lines between secular Jews and religious Jews, ultra-Orthodox Jews who will serve in the military and those who will not, Arabs and Jews, settlers and everyone else. Its parliamentary system, designed to give a voice to minorities, ends up playing a part, giving disproportionate power to small parties.

But Mr. Netanyahu’s style has done much to influence the tone and rules for political warfare since he first became prime minister in 1996. He has championed a populism not seen since Menachem Begin was prime minister in the early 1980s, and he has perfected it, critics say, by invoking external enemies and identifying a parade of internal scapegoats to stoke fear.

“He thrives on dividing people — exactly like Trump,” Mr. Avineri said.

The result has increasingly been to turn adversaries into enemies.

For many Israelis, the ugliness hit a new low last year when, at an emotional Knesset committee hearing on the 2014 Gaza war, two members of Mr. Netanyahu’s Likud Party got into a shouting match with two bereaved parents, calling one of them a “liar.” Mr. Netanyahu, who attended the hearing, sat silently. Only afterward did his office rebuke the lawmakers.

Some, including in Israel’s national security establishment, worry that Mr. Netanyahu has practiced partisanship at the expense of the country’s long-term interests. He placed a large bet on the Republican Party’s coming to power in the United States, embracing Mitt Romney then Donald Trump, and pointedly snubbing President Barack Obama. The bet paid off eventually but it also accelerated the trend of support for Israel breaking down along American partisan lines — a dangerous shift for American Jews and Israel alike.

In fairness to Mr. Netanyahu, Israel faces very real external enemies. While its strategic situation has improved dramatically since its more vulnerable early days, Mr. Netanyahu has also been steering the country through a turbulent period in the Middle East, with Iranian-backed proxies approaching Israel’s borders, neighboring Syria disintegrating into chaos, and the beleaguered Gaza Strip unraveling under Israel’s own pressure and Hamas’s control.

“Everyone thought their son or grandson wouldn’t have to go in the army,” said Moshe Arens, a former Likud defense and foreign minister. “Now it seems like my great-grandson or daughter will have to go in the army. This is the reason why so many people are supportive of Netanyahu,” he said. “They think he’s doing a good job on security, which most people in Israel worry about. Everything else is secondary.”

The red-meat, anything-goes language of Israeli politics today also springs from changes in its electoral system that took time to reveal their more damaging effects. The advent of party primaries in the 1990s, meant to replace smoke-filled rooms with a more open and democratic way of choosing leaders, created incentives for lawmakers to play to their core audiences rather than seek common ground — a phenomenon with which Americans are well acquainted.

Yet Mr. Netanyahu’s Israel also lacks the sense of a unifying national mission that characterized the country’s first 50 years, when it was building itself up from the sand, absorbing waves of diaspora immigrants and defending itself in a series of existential wars, days when its prime ministers wore frumpy clothes and lived modestly, as if they wouldn’t know a payoff if it landed in their palms.

Even his detractors credit Mr. Netanyahu with presiding over the beefing up of Israel’s now-muscular economy, avoiding risky military adventures, and putting his warnings against a potentially nuclear Iran on the international agenda. But he has managed to take peacemaking with the Palestinians off his own agenda, with the help of a weak and internally divided Palestinian leadership.

To younger voters on the Israeli left, eager for a turn at power for the first time since 2001, Mr. Netanyahu’s demurrals have left peacemaking the most urgent unfinished business of the Zionist project.

“Our generation still has an important mission, and that’s that Israeli society and democracy can have a real future,” said Stav Shaffir of the Labor Party, who in 2013, at age 27, became the youngest woman elected to the Knesset. “Our democracy depends on our security, on a Jewish majority, so we need a separation from the Palestinians and a two-state solution.”

Ms. Shaffir said that while the Israeli right wing included “radical extremist voices, with a very strong lobby in the government, who want annexation” of West Bank territory, by and large, Mr. Netanyahu’s coalition seemed unable to articulate an overriding vision.

“I think their only mission today is to stay in government,” she said. “They want the power but that’s about it.”

Ideologically, Mr. Netanyahu’s government has been pulling further to the right like a lopsided team of horses. The moderates are mostly gone from Likud. Mr. Netanyahu, a savvy politician and a pragmatist, is usually the one to put the brakes on the rightward acceleration, such as staving off demands to annex parts of the West Bank. Yet the perennial competition for votes with the far-right Jewish Home party prevents him from resisting with greater gusto.

At the same time, Mr. Netanyahu seems mindful of the need to appeal to the large centrist constituency that is now gaining at the right’s expense.

Mr. Netanyahu’s Israel has seen less partisan moments, like the social protests of 2011 that cut across party lines and were a fleeting reminder of what it could mean for the country to come together in peacetime. Tel Aviv liberals and the ultra-Orthodox stood shoulder to shoulder, demanding answers for the soaring cost of living.

But its energy quickly dissipated. Protest leaders like Ms. Shaffir entered politics; a centrist politician, Yair Lapid, effectively adopted the movement’s agenda. Ordinary people went back to their corners, screaming on Twitter, but mostly to the like-minded.

Now, Mr. Netanyahu has at least unified Israelis around a topic. For the next few months, they can argue about what should become of him.