Washington CNN  — 

This never happens.

U.S. presidents and Israeli prime ministers, however sharply they disagree, simply do not take public pot shots at one another for the world to see. Until now.

Six years of petty insults between President Barack Obama and Prime Minister Benjamin Netanyahu sensationally burst into the open Tuesday in an extraordinary display of Washington political theater, produced by a combination of the alarming threat of an Iranian nuclear bomb, the cliffhanger climax of U.S. diplomacy with Tehran and the hyper-partisan politics in both nations. The legacies of two political giants were on the line, and the fact that neither ceded any ground has serious implications for already strained U.S.-Israel relations.

Netanyahu’s combative – and at times poetic – address to the U.S. Congress was more than a critique of Obama’s Iran policy. It was a detailed repudiation of the U.S. leader’s entire approach to the Middle East and the very idea of talking to the Islamic Republic, which the Israeli leader said was waging a “deadly Game of Thrones” for regional hegemony. Engaging Iran has been an Obama goal since he was a presidential candidate, but the Israeli leader set out to prove his American counterpart is naive about the dangers of the Middle East and the treacherous forces that are tearing it apart.

Obama’s rebuttal

Two hours after Netanyahu left his grand stage, Obama offered his rebuttal, from his own fabled political pedestal – the Oval Office. He dismissed the Israeli leader’s speech – possibly the signature moment of his long political career – as “nothing new” and castigated him for not laying out a viable alternative to the intricate talks between world powers and Tehran to stop Iran from getting the bomb.

It’s a public confrontation that has been brewing for years. But it has more often played out in background briefings, awkward photo ops and tense body language than dueling public statements that reveal the reality that Netanyahu and Obama have never clicked. While respecting, and often publicly glorifying, the bond between the United States and Israel, they’ve feuded behind closed doors about Obama’s choice to use carrot-and-stick diplomacy rather than unrelenting pressure and even tighter sanctions to thwart Iran’s nuclear program and about two failed administration efforts to broker Middle East peace.

READ: Did Netanyahu change some minds?

While the U.S. and Israeli governments have certainly fallen out in the past, this clash is different.

“This is big,” said Robert Danin, senior fellow of the Council on Foreign Relations. “There is something qualitatively different taking place.”

Israel’s suspicion has been simmering for years, following the president’s vow to forge a “new beginning” with the Muslim world in Cairo at the beginning of his presidency, the administration’s pursuit of a secret U.S. diplomatic track with Tehran and Obama’s decision to break 30 years of silence in U.S.-Iran relations by calling President Hassan Rouhani and writing letters to Supreme Leader Ayatollah Ali Khamenei.

The implication of Netanyahu’s speech was stunning. Here was an Israeli prime minister, effectively accusing the president of signing up to a deal that would not eradicate Iran’s nuclear program but that could allow Iran to press ahead for a nuclear arsenal it could use to make good on its threats to destroy the Jewish state.

That was tough for some Democrats to process.

‘I thought that was wrong’

Netanyahu “used the chamber to put him in a position that the president is often in, addressing the Congress at the State of the Union,” Democratic Rep. Steve Cohen of Tennessee told CNN. “This puts him on equal footing with the President of the United States. I thought that was wrong.”

House Democratic Leader Nancy Pelosi, a faithful supporter of Israel, said she had been “near tears” as Netanyahu spoke and accused him of showing “condescension” to the United States.

READ: 58 members of Congress skipped Netanyahu’s speech

The White House has long thought Netanyahu to be in cahoots with Obama’s political foes in an effort to torpedo his foreign policy.

“For the administration, this was the smoking gun, the proof that in fact there was this collusion between the Republicans and Israel,” said Danin.

But Israel was unapologetic.

“I know that (the speech) creates some tensions with the administration,” Yuval Steinitz, Israel’s Intelligence Minister, told CNN’s Christiane Amanpour. “Nobody can expect little Israel to keep silent on such a vital issue,” he said.

Scripture

In his address to Congress, Netanyahu cited scripture and the Jewish holiday of Purim, which commemorates the thwarting of a powerful Persian viceroy’s attempt to destroy the Jewish people.

“Today, the Jewish people face another attempt by yet another Persian potentate to destroy us,” Netanyahu said, accusing Khamenei of spewing the “oldest hatred.”

“He tweets in English that Israel must be destroyed,” said Netanyahu, who was interrupted repeated by lusty cheers from Republican lawmakers and some Democrats. “That deal will not prevent Iran from developing nuclear weapons. It would all but guarantee that Iran gets those weapons, lots of them.”

READ: Netanyahu: Deal will pave way to Iranian nuclear bomb

Netanyahu set out to dismantle point by point the assumptions underlying the international effort to convince Iran to throw open its nuclear installations in return for a lifting of punishing international sanctions. He said Iran would never change, could not be trusted and was likely to use a 10-year sunset on any agreement to go nuclear down the road.

He said Tehran was bent on simply gobbling up wide swathes of the Middle East, slamming its “goons in Gaza, it’s lackeys in Lebanon, its Revolutionary Guards on the Golan Heights,” and saying it wanted to control of Yemen, Syria and Iraq. All of this was to underline the U.S. should not be hoodwinked into seeing Iran as an ally against ISIS.

“The enemy of your enemy is your enemy,” Netanyahu said.

Obama made his move on Iran after the comparatively moderate Rouhani was elected in 2013, but Netanyahu said it had been business as usual in Tehran: “Rouhani’s government hangs gays, persecutes Christians, jails journalists and executes even more prisoners than before,” he said.

A senior White House official, speaking on condition of anonymity, ascribed a darker motive to Netanyahu’s train of thought.

“The logic of the prime minister’s speech is regime change, not a nuclear speech,” the official said, going on to refute Netanyahu’s implication that the White House had naively been drawn in by the Islamic Republic.

“The administration does not trust the Iranian regime,” the official said.

Obama is often laconic and loose in photo ops, but on Tuesday he leaned forward in his chair, animated and intense, saying people should not criticize a nuclear deal before it had been reached and that Netanyahu’s critique of an interim deal with Iran had not panned out.

No ‘viable alternatives’

“The prime minister didn’t offer any viable alternatives,” Obama said, arguing that in the absence of a deal Iran would simply speed up its nuclear program.

As Netanyahu headed back to Israel on Tuesday night, conversation was already turning to the lasting impact of his speech.

Karim Sadjadpour, an Iran analyst at the Carnegie Endowment for International Peace, suggested that Netanyahu’s presentation could cause political problems for Obama.

“It makes it much more difficult to sell this deal to the U.S. public,” he said.

CNN contributor Guy Ziv of American University said that fallout was going to make the already bruised relations between Obama and Netanyahu worse.

“I don’t think the speech is going to do any sort of damage to the Iranian nuclear program, but we know it already has done some damage to U.S.-Israel relations,” he said.

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