(Bloomberg Opinion) -- The collapse of Bibi Netanyahu's plans for a governing coalition is not something he saw coming. This in itself marks a rare failure in what has long been an unparalleled political intelligence. Netanyahu will now be forced to re-fight a battle he thought he had won, this time on more treacherous terrain.

Ostensibly, the coalition was lost because former Defense Minister Avigdor Lieberman refused to allow his five-member faction to join. He claimed that he was violating his pledge out of principle. The ultra-orthodox coalition members oppose a law making a small number of yeshiva students eligible for military service. Lieberman wants the law. The army doesn't need or want these kids, as he well knows. The issue, his says, is "symbolic," a protest against the growing influence of rabbinical parties. 

It is a genuine concern, but I doubt it was foremost in Lieberman's thinking. Lieberman, after all, has been doing business with the rabbinical parties for many years. Shas leader Aryeh Deri seemed shocked by his new concern about the ultra-orthodox political agenda. “He’s always been friendly to our communities,” he says.

 No, this is personal. Lieberman and Netanyahu have been frenemies since 1988, when Bibi hired the former bar-room bouncer as an assistant. In those days, Netanyahu sometimes referred to Lieberman as his "zhlub," a Yiddish word meaning muscle-head.

This stung. Lieberman may look like the villain in a Soviet spy drama, and his Russian accent is easily mocked, but he is smart, astute and more sensitive than he appears. In his day-after press conference, Lieberman reminded the media that he was once an aspiring poet.

Lieberman has come a long way since his bouncer days, and he owes a great deal to Bibi. But he has also suffered the humiliations of a prolonged junior partnership under an egotistical patron. This looks like payback.  

Lately, he began seeing his mentor making unforced errors. For the Bibi of a decade ago, the coalition would have been a two-inch putt. Watching his inattention to coalition building, Lieberman concluded that the boss -- wrapped up in corruption charges against himself and his wife, inattentive to the concerns of his party colleagues and evidently unable to control the internet misbehavior of his 27-year-old son Yair — was ready to be taken down.

Bibi thinks this is just a blip and he will win the September election. Math is on his side. The majority of Israeli voters are right-wing. A poll taken on the day after the coalition collapse shows virtually no change between right and left. But there was a significant bump for Lieberman’s party too. It’s just one poll, but it could mean that, after the next election, Lieberman could block Netanyahu from a new government.

If that happens, Likud (which Lieberman has labeled a cult of personality) could very well decide that its venerated leader can be dispensed with. It would be an inglorious ending to Bibi’s career and a big step for Lieberman, who has ambitions of his own. 

The second election of 2019 will be not a debate about borders, the economy or Iran, but a grueling, uninhibited grudge match between two men with an intimate knowledge of each other’s weaknesses. It is a challenge Bibi will face while simultaneously fighting charges of corruption before judges furious at his attempt to turn the public against the justice system, coping with the more erratic members of his household and watching for signs of an emerging Likud Brutus.   

He will also have to keep running the country. On the day after the coalition debacle, he met with Donald Trump's son-in-law and adviser Jared Kushner and other American officials to discuss “deal of the century” diplomacy. The plan itself won’t be controversial in the election — the major opposition party doesn’t fundamentally disagree — but the work that goes into it will be time consuming.

A political campaign too is exhausting. Two campaigns within a few months, especially in the heat of an Israeli summer, for a leader with a full-time job or rather two (Bibi is also Defense Minister) will be an ordeal. He turns 70 a month after the election. Lieberman is 10 years younger.

Bibi has been in office now for a decade.  That’s long enough. He has been, on the whole, a very effective prime minister. The country has flourished under his leadership and the center-right ideology he imported from the U..S has become the default in Israeli politics. But even good prime ministers reach an expiration date. Bibi may be reaching his.

To contact the author of this story: Zev Chafets at zchafets@gmail.com

To contact the editor responsible for this story: Therese Raphael at traphael4@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Zev Chafets is a journalist and author of 14 books. He was a senior aide to Israeli Prime Minister Menachem Begin and the founding managing editor of the Jerusalem Report Magazine.

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