Israeli Prime Minister Benjamin Netanyahu, right, turns to the media as he and U.S. Defense Secretary Ashton Carter prepare to go upstairs to meet at the prime minister's office in Jerusalem on Tuesday, July 21, 2015. (AP Photo/Carolyn Kaster, Pool)

In the aftermath of the deal over Iran's nuclear program announced in Vienna last week, attention immediately centered on the reaction in one country that was never a direct party to the talks: Israel.

Israeli Prime Minister Benjamin Netanyahu was swift and uncompromising in his criticism, declaring the accord a "historic mistake," and reiterating his long-standing opposition to rapprochement with the Islamic Republic. His anger was echoed by his center-left political opponents in the Israeli parliament.

[Netanyahu wants 'permanent' conflict with Iran, says Britain's top diplomat.]

But while Israel's politicians may be singing from the same song sheet, others are less sure. Prominent members of the country's security establishment have come out at various stages of the negotiations in support of the Obama administration's efforts. Some of these men have been consistently vocal in their opposition to Netanyahu's hard-line rhetoric, which included a controversial speech to the U.S. Congress earlier this year.

Here's a rundown of some of their observations.

In an interview this week with the Daily Beast, Ami Ayalon, former head of the Shin Bet, or Israel's top domestic security agency, suggested that Israel's politicians were playing "with fears in a fearful society."

He praised the Vienna agreement as a useful measure to curb the Iranian threat.

"When negotiations began, Iran was two months away from acquiring enough material for a [nuclear] bomb. Now it will be 12 months," Ayalon said, adding that many of his compatriots were not seeing the strategic advantage of the deal. "Israelis are failing to distinguish between reducing Iran's nuclear capability and Iran being the biggest devil in the Middle East."

Here's what's in the Iran nuclear deal, and what happens next. (Gillian Brockell and Julio C. Negron/The Washington Post)

When a framework agreement was reached in Lausanne, Switzerland, in April, Efraim Halevy, former chief of the Mossad, Israel's spy agency, hailed Obama's victory. In an op-ed in the Yedioth Ahronot, Halevy listed some of the key provisions of the deal, which included a strict regime of inspections and the neutralizing of Iran's key nuclear facilities.

[How the Iran deal works.]

"Anyone who has followed events in Iran in recent decades or has studied the matter has to admit truthfully that he never believed Iran would ever agree to discuss these issues," he wrote, "let alone agree" to the measures imposed on Tehran by the world powers.

The alternative would be military strikes, which would plunge the region in deeper insecurity and would likely not be successful, Halevy said in an interview with Israeli radio in April.

"If we think that the monitoring won’t be effective, the only other option is a military campaign that will only set back the Iranians for a limited number of years," he said.

Instead, argued Amos Yadlin, a retired air force general and former head of Israeli military intelligence, "there is a chance to set Iran back by many years."

The final agreement, Yadlin told Israeli radio in April, would not legitimize Iran's misdeeds on the international stage, which include actively supporting militant proxy organizations in the Middle East deemed terrorist organizations by the United States and its allies.

"Iran can’t go back to being a legitimate member of the family of nations if it doesn’t stop all its activities that are not included in the agreement — its subversive activities, its support of terror groups, weapons proliferation," said Yadlin, who while not a fan of the deal has called for Israeli calm and cooperation with Washington. "The Americans took a strategic decision ... to deal with the nuclear issue as a separate matter and to not tie it to the other issues."

The American effort has not been appreciated by Netanyahu, who has become a fellow traveler with hawkish Republicans in Washington. His decision to wade into partisan politics and alienate the Obama administration, said former Mossad chief Meir Dagan earlier this year, "caused Israel the most strategic damage when it comes to the Iranian issue."

Israel has spent the better part of a decade working against Iran's nuclear program, campaigning for sanctions and clandestinely attempting to sabotage Iranian projects. But Netanyahu's loud hectoring, Dagan suggested, was pushing Israel toward a situation of military confrontation.

In 2011, Dagan poured cold water on the idea of Israeli strikes against Iran's nuclear program. In a speech, he said bombing Iran "would mean regional war, and in that case you would have given Iran the best possible reason to continue the nuclear program." He went on: "The regional challenge that Israel would face would be impossible."

The current arrangement, authored in Vienna, would likely be preferable.

Clarification: The headline on earlier versions of this post – “How the Iran deal is good for Israel, according to Israelis who know what they’re talking about” – did not reflect the nuance of some of the positions of Israeli officials cited. The headline has been changed to reflect this. Additionally, the post was updated soon after publishing to include language noting that Amos Yadlin, the former head of Israeli military intelligence, is “not a fan of the deal,” but that he has “called for Israeli calm and cooperation with Washington.”

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