It was November 2013 and Efraim Halevy, the former head of the Mossad, was in Istanbul for an international conference on science and security.The P5+1 talks with Iran in Geneva were scheduled to begin in just a few days, but before flying there, Iranian Foreign Minister Mohammed Javad Zarif decided to pop into Istanbul to address the conference.More than 100 people were in the room when Zarif took the stage alongside Ahmet Davutoglu, Turkey’s foreign minister at the time. While Halevy didn’t know for certain, his intuitive espionage skills left him with little doubt that Zarif knew there was a former head of the Mossad among the crowd in front of him.The Iranian spoke for close to an hour, about the region, his country’s economic situation and expectations from the upcoming talks. The world, the -educated Zarif said in perfect English, had become a “global village” in which one country cannot be secure or have economic prosperity if other countries do not enjoy the same.When Zarif finished speaking, he agreed to take questions from the audience. Halevy, who had been impressed by the Iranian’s remarks, thought to ask if there was anything Zarif could say to allay concerns in Israel and Saudi Arabia, but figured there was no way he would answer a question posed by a former high-ranking Israeli official. So, Halevy gave the question to an American colleague to ask it in his place.Even so, Zarif ignored the question. Instead, just after the question was asked, he looked at his watch, announced that he was late for another meeting, and abruptly left. The question about Israel remained lingering in the air.Nevertheless, Halevy walked away impressed. Zarif, he told me this week, was definitely not a Zionist or even a member of Peace Now. But, the former Mossad chief said, he walked away thinking that there was room to open a dialogue with the Iranians. “You need to talk to your enemies,” he told me.I went to see Halevy to get his impressions on Prime Minister Benjamin Netanyahu’s efforts to convince President Donald Trump to undo and revise the 2015 nuclear deal with Iran.Halevy served as head of the Mossad from 1998 to 2002, working under three prime ministers – Benjamin Netanyahu, Ehud Barak and Ariel Sharon. Born in London in 1934, he moved to Israel in 1948 and was recruited into the Mossad in 1961 where he slowly climbed the ranks, starting first as an intelligence analyst.Since leaving the espionage world, Halevy has not shied away from taking controversial positions on matters of national security.Back in 2011, he came out in full force against Netanyahu and Barak who appeared at the time to be pushing for an Israeli strike against Iran’s nuclear facilities. While Iran’s nuclear program was a “serious threat” and needed to be stopped, Halevy said that it was not a threat of an existential nature and that Israel did not need to attack.In more recent years, he has become a vocal advocate for direct talks between Israel and Hamas. “The more that Hamas is permitted inside the tent, the better the prospects of a modest (yet historic) success,” he wrote in The New Republic in 2010.Since the beginning, Halevy has supported the nuclear deal.Back in 2015 he was one of a handful of former top defense officials – alongside former Shin Bet (Israel Security Agency) chief Ami Ayalon and Uzi Eilam, the former director of Israel’s Atomic Energy Agency – who urged Netanyahu to stop fighting the Obama administration and to accept the nuclear deal with Iran. Halevy decided to speak up this week since he believes that Netanyahu is again making a historic mistake in his efforts to overturn the deal. First and foremost, he points out, Iran is abiding by the deal.The same day I met with Halevy, Chairman of the US Joint Chiefs Gen. Joseph Dunford confirmed at a Senate hearing that Iran is in fact fulfilling its part.“The deal that was achieved was beyond the realistic expectation even here in Israel,” Halevy said. “This is not to say that the ultimate deal is the exact manifestation of Israel’s most vital interests.”Nevertheless, he explains, the nuclear agreement was always meant to deal only with Iran’s nuclear program, not its missile development or its support of terrorist organizations throughout the region. For Israel to now demand changes to the deal because of Iran’s support of Hezbollah or its growing presence in Syria is simply wrong, he stressed.The reason is simple, he continued. “The address is not Washington.It is Moscow.”Why Moscow, I asked. Halevy explained: The Russians, he said, are the ones who are allowing Iran to deploy in Syria. They are the ones turning a blind eye to the transfer of weaponry to Hezbollah and they are also the ones who supplied the Iranians with advanced weapon systems like the S-300 air surface-to-air missile system displayed at a military parade in Tehran last week.“But for reasons which have never been revealed we don’t know everything that is going on with Israel and Russia,” he said. “The fact is that we don’t speak out against the Russians.We speak against the people who have nothing to do with this, but the S-300 wasn’t supplied by the Pentagon.”Imagine, Halevy continued, if the Obama administration would have sent sophisticated weaponry to the Iranians. “We’d go mad,” he said. “We are shouting from the rooftops about what the Iranians are doing, but the Russians are at our doorstep and we are not doing anything.”“Why is Washington the recipient of all of our complaints with what’s happening in Iran all the time, when the real address is not even mentioned?” Halevy asked.But, I challenged the former Mossad chief, even if Moscow should be the address right now, there are still problems with the nuclear deal that need to be addressed such as the sunset clause which, once the deal expires in 10 years, will put the Iranians in a position to build a bomb in almost no time.“That is eight years away,” he insisted. “Who knows what will be in another eight years. They are not going to renegotiate it and no one wants to renegotiate, so what you are doing now instead is sowing dissension between the US and Russia and within the P5+1.”I am not sure Halevy is right, but he makes two important points. The first is that Israel needs to stop the hysteria. Iran is a challenge, a very serious one. But it is not an existential threat.To call it one, as some of our leaders have done in recent years, is to give the Iranians a status that they do not deserve. Israel is a powerful country with unbelievable means at its disposal to eliminate threats and defend against them. By talking in apocalyptic terms, Israel is giving its enemy a capability it does not deserve.The second point is that the Israeli public deserves to know more about what is happening between Jerusalem and Moscow.Netanyahu has met with Putin six times over the last two years, but despite this ongoing dialogue, Russia continues to play an extremely dangerous role in the Middle East. Its arming of Iran, support for Syria’s embattled President Bashar Assad and refusal to agree to Israel’s request that Iran and Hezbollah leave Syria once the war is over, all combined make Moscow more of an adversary for Israel than a friend.The nuclear deal the world superpowers reached in 2015 was a bad deal, not just for Israel but for the entire world. Even if the Iranians abide by the accord for the next eight years they will ultimately be able to get the bomb, which would give them a capability that could potentially pose an existential threat to Israel.The problem though is that if Iran decides to build nuclear weapons, it will eventually succeed. It’ll come at a price but it will be difficult to stop. What is happening now with North Korea is all the proof we need to understand that. In the meantime, while the deal might be bad, as Halevy points out, it is also a done deal.That is the main reason the IDF brass quietly supports keeping the nuclear deal in place. Not having to invest in plans to attack Iran’s nuclear facilities has allowed the IDF to invest its resources in other capabilities that needed a boost and some attention while countering some of the other, more immediate, threats Israel faces.In addition, a decade of quiet – assuming Iran continues to abide by the deal – is not something that can be taken for granted. In a volatile region like the Middle East, every day of quiet is a blessing.