Israeli Prime Minister Benjamin Netanyahu and Avigdor Lieberman were political allies until recently.Amir Cohen / Reuters

JERUSALEM—Israel’s politics are wild and chaotic. Its electoral system is remarkably reliable. In the past seven decades, 20 parliamentary elections yielded relatively well-functioning governments. The 21st was a different story.

Benjamin Netanyahu’s failure this week to form a coalition, followed by his unprecedented move to dissolve the Knesset and go for an early election, just seven weeks after the previous one, is legal, but flies in the face of Israeli political tradition.

The dynamic of the next election, to be held in September, is impossible to predict. Will Israeli voters, to avoid further political instability, turn away from smaller parties and enhance Netanyahu’s majority? Or will they identify the frantic maneuvering of a prime minister facing multiple corruption indictments as the source of chaos and punish him at the polls? Will the demoralized center-left opposition finally rejuvenate itself? And how will voters treat Avigdor Lieberman, the former hard-line defense minister, who sparked this crisis by refusing to join Netanyahu’s coalition?

Beyond these short-term questions, however, the earthquake of the Knesset’s premature demise may also herald a tectonic shift in Israel’s political map.

Lieberman’s challenge to Netanyahu is personal. But the matter of principle he chose to base his challenge on threatens the power structure that has kept Netanyahu’s party, Likud, in power—its steadfast alliance with the religious parties. As a condition for his nationalist party joining the government, Lieberman demanded that the new Knesset pass a law setting quotas for the number of yeshiva (Jewish religious seminary) students drafted into the army. Ultra-Orthodox parties that had already allied with Netanyahu demand the right of students to continue studying uninterrupted.

For a country where most (Jewish) Israelis are compulsorily enlisted, the exemption for yeshiva students has been an issue all governments have wrestled with and compromised on. In making it a wedge issue, Lieberman has put in question the political alliance between the right-wing and the religious camps. He repeatedly said his party was “prepared to serve in a national government. Not in a Halacha [rabbinical law] government.” It’s a cynical, even hypocritical, move by a veteran politician who has served in many a cabinet over which the rabbis held considerable sway. He senses that Netanyahu’s reign is almost over and is striking at the base of the alliance that has kept the prime minister in power to hasten his downfall.

For the past decade, in which Netanyahu has governed uninterrupted, religious parties have seemed an almost integral part of the right wing: When the Israeli media present polling or actual election results, they now automatically include the Knesset seats of the two ultra-Orthodox parties in the right-wing bloc. This is a relatively recent development. From the first Zionist Congress in 1897, the main parties were led by secular Jews. This was true of the Socialist-Zionist parties that dominated the Zionist movement from the 1920s onward and were the main force in the foundation of Israel in 1948, as well as their rival, the right-wing Zionist-Revisionist movement, the forerunner of Likud.

The smaller, religious parties fell into two groups. There were those, referred to in Israel as “national religious” and among American Jews as modern-Orthodox or just plain Orthodox, who believed the Zionist ideal of rebuilding a Jewish state in the historical homeland was compatible with traditional Judaism. Their politicians were initially moderate, allying themselves in coalition with the mainstream Socialist-Zionists. In 1967, when the cabinet debated whether to embark on what would be known as the Six-Day War, the national-religious ministers unsuccessfully urged restraint. The war would see Israel occupying the biblical heartlands of the West Bank, releasing a more nationalistic sentiment among the younger members of the national-religious community, the vanguard of the settler movement. On the political field, this meant sharply veering to the right, abandoning the “historic alliance” with the Labor Party, and placing themselves firmly on the right as Likud’s partners.

But most of the rabbis of the ultra-Orthodox, or Haredi, Jews initially saw the secular Zionist movement as heretical. Over decades, their attitude became more ambivalent, and most of the rabbis supported Haredi representatives entering the Knesset and government to safeguard their community’s interests. The Haredi parties didn’t pick sides. They sat in Likud and Labor coalitions, and in opposition, depending on what was on offer. To this day, they insist they are neither right nor left wing. Yet as the Israeli left was more stridently secular, while many on the right were traditional or observant, the ultra-Orthodox slowly drifted toward the Likud camp. Still, until a decade ago, they preserved their independent status as potential kingmakers, keeping options open on both sides.

One of Netanyahu’s greatest political achievements has been cementing the alliance between Likud and these religious parties. Netanyahu does not keep any of the commandments of the Torah. His ideology is secular Jewish nationalism, and those who know him well, many of whom I interviewed for a biography of Bibi, insist he is an atheist, though he’s never admitted it publicly. But unlike other secular politicians, he has never shown any interest in separating religion from state or curbing the rabbinical hegemony on certain sections of Israeli life, such as family law. Netanyahu focuses solely on geopolitics, security, and macroeconomics, partly for political expediency. He is happy to give the ultra-Orthodox leadership full autonomy to run their lives in any way they see fit.

Netanyahu is prepared to give the ultra-Orthodox blanket exemptions from national service and even allow them to hold sway over matters that affect other Israelis, such as control of marriage and divorce and the definition of Jewish identity, crucial to a state that grants automatic citizenship to anyone who can prove to be Jewish. In return, he expects their political support. Under Netanyahu, the Haredi politicians have foresworn their kingmaker status. Because of their higher birth rates compared with those of the general population, the size of their political representation is gradually growing, and the built-in Knesset majority of a right-wing-religious bloc is all but assured.

That arrangement is now being challenged by Lieberman. Born in Kishinev, in the former Soviet Union (today Chisinau, the capital of Moldova), and still speaking with a heavy Russian accent, Lieberman also has the perfect constituency on which to base such a strategy—the large community of Israelis who immigrated from the former Soviet Union. “They are the one exception to my main polling law of Israelis: that the more right-wing you are, the more religious you are as well,” Dahlia Scheindlin, a pollster and political strategist, told me.

The “Russian” Israelis—those born in the former Soviet Union, or born in Israel to two Russian-speaking parents—make up about one-tenth of the population, according to Scheindlin’s research. In addition, she says, “the dividing line between Israelis on issues of religion and state doesn’t totally run in parallel to the left-right dividing line on issues of diplomacy and security. There are many right-wingers who are less supportive of religious legislation.”

There are Israeli parties that in the past campaigned on curbing the power of the ultra-Orthodox, but these usually came from the political left or center. No right-wing party has championed these issues since Netanyahu first came to power, in 1996. Lieberman, who is now emerging as the first serious rival to Netanyahu on the right in a decade, is gambling that there are enough right-wingers fed up with the alliance with the religious parties who will redraw the map of Israeli politics, making him the new kingmaker with the power to unseat Netanyahu.

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