Benny Gantz, man in the middle squeezed out by Israel's Netanyahu

By James Mackenzie

JERUSALEM (Reuters) -In the traumatic aftermath of the Oct. 7 attacks on Israel, as hundreds of thousands of Israeli reservists rushed to join the ranks to fight Hamas, Benny Gantz said he felt it was his duty to join the war effort.

"This is not a political partnership I am in," the centrist former general told a group of reporters, shortly after agreeing to join Prime Minister Benjamin Netanyahu in an emergency wartime government of unity. Instead, it was "destiny".

"Hamas started the war but Israel will win it. There is no doubt about it. We will win this war," he said.

Now, eight months in, the early confidence of those remarks made as Israel was starting to get back on its feet following the shock of Oct 7, appears to have ebbed.

Having tangled repeatedly with the prime minister and the hardline nationalist religious parties in his coalition, Gantz has quit, three weeks after laying down a deadline for Netanyahu to come up with a clear postwar strategy for Gaza.

His departure will remove one of the few in Israel's government who still appeared to enjoy the confidence of a U.S. administration whose frustration with Netanyahu has become ever more evident as the war has gone on.

Even before the deadline, he had appeared increasingly unhappy with the government, quarrelling over issues ranging from the army leadership to opening a path towards a two state solution with the Palestinians. In April he called for new elections to be held in September, only to see the call rejected.

The commanding lead over Netanyahu he and the centrist party he leads once held in the opinion polls has shrunk, and, with the ruling coalition's parliamentary majority still solid, his political future is unclear.

A former paratrooper who grew up on a kibbutz and commanded the elite Shaldag commando unit, Gantz, the son of a Holocaust survivor, spent most of his career in the military. As army chief of staff in 2012, he oversaw an eight day-operation in the Gaza Strip that began with the killing of the chief of Hamas' military wing in Gaza.

He served as defence minister in the previous government and for months, his hawkish military credentials allied to his opposition to Netanyahu's divisive campaign to trim the powers of the judiciary last year, made him seem like the natural choice to lead a future government.

He has also been notably more open to the idea of a political settlement with the Palestinians than either Netanyahu or his right-wing allies like Finance Minister Bezalel Smotrich or National Security Minister Itamar Ben-Gvir, for whom a Palestinian state is an anathema.

Gantz, while mistrusting many Palestinian leaders, always seemed more willing to accept that Israelis and Palestinians eventually had to learn to live in the same region. "No one is going anywhere," he said.

With relations between Washington and Israel at their lowest point in years over the conduct of the war and the mounting casualty toll in Gaza, Gantz, along with Defence Minister Yoav Gallant, appeared to be one of the few in government trusted by U.S. President Joe Biden's administration.

Earlier this year, he visited Washington, infuriating allies of Netanyahu, who has so far not received an invitation to the White House. But his political instincts have been no match for Netanyahu, one of Israel's wiliest operators, who rode out the rebuff from Biden and is due to address both houses of Congress next month.

Many on the left thought Gantz and his centrist partners should have left the government sooner. Others, like Einav Tsengaukar, the mother of one of the Israeli hostages left in Gaza, who begged him to stay and try to agree to a deal to get the hostages home, wanted him to remain. But in the end, his departure appeared inevitable.

Aviv Bushinski, a former communications adviser to Netanyahu, said in the end, Gantz's own attempt to pressure Netanyahu had only succeeded in paving the way for his own exit.

"Benny Gantz cornered himself because he cannot retreat, he cannot back off from the ultimatum."

(Reporting by James Mackenzie, Editing by William Maclean)