In philosophical terms, that means grasping the existential threat that is the dark birthright of the Israeli Jewish population, said Mitchell Barak, a pollster in Jerusalem who worked for Mr. Netanyahu before he became prime minister.

“He’s always been, and always will be, the prophet of doom,” Mr. Barak said of his former employer. “For the Jewish population that sees Jews being persecuted throughout that world, he’s the guy who talks the talk.”

Even when Israel is comparatively placid on the security front, as it has been this year, Mr. Netanyahu is able to “geniously exploit” the situation, said Henriette Dahan Kalev, an emeritus professor of political science at Ben Gurion University.

“They are so much occupied with their everyday lives and so tired with scandals,” said Ms. Dahan Kalev, “saying that you have to allow the politicians to do their work, and to constantly investigate them and threaten them might hinder them from doing that.”

Mr. Netanyahu, 66, may also be shielded by the sheer tortuousness of some of the shenanigans he has been accused of. In a case in 1997, it was claimed that he had appointed an attorney general solely to obtain a plea bargain in a corruption case involving a political ally — in hopes of gaining support from that ally for an Israeli troop withdrawal from most of the West Bank city of Hebron. Prosecutors said they had a “tangible suspicion” of wrongdoing in the case, but not enough evidence to bring charges.

“As far as I am concerned, and I think as far as the majority of the public in Israel is concerned, this affair is behind us,” Mr. Netanyahu said at the time, although few believed he was right.

And so it went. Some cases involved alleged gifts or improper foreign donations to Mr. Netanyahu and his family. Raviv Drucker, an investigative journalist at Israel’s Channel 10, said one case he had reported on — known as Bibi Tours, using the prime minister’s nickname — had started from claims that in the hiatus between premierships, wealthy businesspeople and others financed trips for Mr. Netanyahu and his family.