A cloud from an explosion rises near the Syrian village of Al' Rafide at the border with Israel May 7, 2013.(Uriel Sinai/Getty Images)

The Israel Defense Forces Chief of Staff, Lt. Gen. Benny Gantz looks absolutely exhausted these days. Gantz, who was appointed to his job almost as an afterthought in February 2011, after a particularly poisonous battle within Israel’s military leadership, has never radiated a very lively aura. It may be a matter of character, or age, or just the fact that he had been called back into office after deciding to retire, but the IDF’s commander often seemed to be gliding through his term during the first two years in office. All this has changed: The man, it is rather clear, is not getting much sleep. His aides, well aware of this, try to enhance the boss’s alertness by providing him a constant supply of black coffee. Even the Israeli media had taken note. The result: a rather heated debate over the required rules of courtesy at the chief of staff’s office and whether those rules offend women officers.

Menachem Begin once famously maintained that “you do not ask a gentleman where he spent last night,” but Gantz’s chief reason for exhaustion is pretty clear: the deteriorating situation in Syria. While Israeli and American politicians pour clichés over the Iranian nuclear threat, the IDF is now more immediately worried about the dangers from Israel’s northern front—the implications of Syria’s civil war in particular. Publicly, Israel is deliberately keeping a very low profile. Even the last two Israeli air strikes (out of three, altogether) in Syria were initiated without any official response from Jerusalem (and since Israeli military censorship laws apply to Israeli journalists, I should add that these strikes only happened according to international sources).

It is reasonable to assume that Israel’s current operations in Syria are not limited to air strikes. Israel’s different intelligence agencies are believed to keep a very watchful eye on our northern neighbor, while various Arab media organizations have constantly claimed that Israel’s elite units frequently operate inside Syria. After Israel bombed the North Korean-made nuclear plant in northeast Syria in September 2007, several Western newspapers reported that Israeli commandos had secretly visited the site beforehand, taking ground samples in order to make sure that the site had indeed been what the intelligence claimed it was.

For decades, Syria had been considered Israel’s fiercest enemy—and also its most feared. Israeli POWs, returning from long periods in Syrian jails, told stories of very brutal methods of torture, a much more aggressive treatment than any experienced from Egyptian jailers. The trauma of the Yom Kippur War in 1973 is still ingrained in Israeli collective memory. For years, the IDF units had prepared themselves for a repeat: Syrian tanks storming through the Golan Heights, threatening to reach the Sea of Galilee; Syrian commandos taking by surprise the IDF’s bases on Mount Hermon. In every war room at the northern command, there used to be a big poster, saying “War Tomorrow.” The IDF’s top brass had genuinely feared this scenario for years, but the concern also served to keep the army on its toes—and allowed the military to expand the defense budget after the relative failure in the war, to establish more divisions and brigades and to keep the reserve units well-trained. Tank crews and infantry units practiced for what was seen as an inevitable war with Syria, while military intelligence teams memorized the names and roles of Syrian division officers—preparing for a full-scale military confrontation that never materialized.

In reality, the Syrian army had long been deteriorating, as its tanks and fighter jets gradually rusted. After the collapse of the Soviet Union, Russia refused to honor huge arms deals with Syria, since Damascus was not able to come up with the required cash. Hafez el-Assad’s original goal—to reach strategic parity with Israel—was eventually abandoned by the Syrian regime, and his son and successor, Bashar, came up with a new strategy. Since Syria could not equal Israel on the military front, it would find new ways to circumvent the IDF’s superiority. The Syrians began to concentrate on defensive weapons and methods that would make it extremely difficult for Israel to attack through the border in the Golan Heights—fortifications, anti-aircraft and anti-tank missiles—while pointing a massive armory of surface-to-surface missiles and rockets at Israel’s towns and cities. The threat, Assad Junior hoped, would be enough to prevent Israel from seeking a direct military confrontation with Syria. Meanwhile, both Assads continued to support Lebanese (Hezbollah) and Palestinian (Hamas and Islamic Jihad) organizations in their ongoing fight against Israel.

Although the new Syrian strategy did not push Israel to surrender the Golan Heights in peace negotiations, it did help to persuade the Israelis to initiate a full withdrawal from southern Lebanon in 2000 and helped Syria maintain its position among members of the radical anti-Israeli camp in the Arab World. Both sides of the Golan border upheld a rather constructive balance of deterrence: Each side remained careful not to appear to be publically provoking the other, and the Syrian border remained one of Israel’s calmest fronts for decades. Every few years, when Israel suspected that the Syrians went too far in supporting Palestinian terrorism, it sent a clear message—by sending fighter jets to fly very low over the presidential palace or by attacking a training camp near Damascus.

And when in 2007 Bashar Assad surprised the world by actually pursuing a nuclear project, the Israelis—according to American and European journalists—reacted by striking and destroying that site from the air. Israel never publicly claimed responsibility for the attack, a tactic that presumably helped Assad ignore it and kept the border calm for the next few years. The shadow war between the two countries has been quite frustrating for Israeli newsmen, who had read in George W. Bush’s and Condoleezza Rice’s memoirs very specific descriptions of this affair, but still cannot—to this day—contribute anything to the discussion.

Yet the larger strategic assumptions that underlay the balance of power on Israel’s borders was altered drastically by that turmoil that some experts still insist on optimistically describing as the Arab Spring. Suddenly, as Israeli scholar Asher Susser had put it so accurately, Israel stopped being afraid of Arab strength and began to be worried about Arab weakness. In Syria, what had started as a local popular revolt in the southern city of Dara’a grew pretty quickly into a terrible civil war, the worst conflict to hit an Arab country since the outcome of the American invasion of Iraq in 2003.

From the Israeli perspective, Syria became a huge problem once the Assad regime began to experience difficulties in controlling the distant provinces—specifically the provinces near the Israeli border. Once the border area became an enclave for extremist, al-Qaida-affiliated groups, Israelis faced a new threat: A failed-state, or a non-state, along the border was a much harder foe to handle than a deterred police state, no matter how brutally its dictator treated his subjects. Whom do you deter when there is no longer an identifiable actor on the other side of the border?

Very quietly, and unofficially, Israeli leaders wish success to both sides. They pay lip service to condemning the regime’s horrors and express their sympathy for the plight of the Syrian people under Assad but do not go out of their way to help the opposition. Israel assumes that if indeed the opposition wins, it would quickly be dominated by jihadist groups, which will soon set their weapons against the Jewish settlements in the Golan Heights. On the other hand, if the fighting continues, so will the deterioration of the Assad forces’ military capabilities. No army would be able to initiate a war against a neighboring country after more than two years of a self-destructive murderous battle against its own people—producing what is almost a win-win situation for Israel.

Yet Israel has its red lines, just like everybody else these days. President Barack Obama defined, rather vaguely, the American red line: The United States would intervene if it has proof that the Assad regime had used chemical weapons. Israel’s red line is very different. It will act, as Israeli leaders have constantly threatened, if important weapons systems are either transferred deliberately from Syria to Hezbollah or fall into the hands of extremist jihadist groups on the rebels’ side. Some Israelis have described the effect of these weapons as “tie-breakers” in Lebanon. This is clearly false, since there is no “tie” between Israel and Hezbollah. But Israel is explicitly nervous about the transfer of chemical weapons, of advanced anti-aircraft systems (such as the Russian-made SA-17 missiles, bombed in January near Damascus, presumably on their way to Lebanon), of coast-to-sea missiles (like the Russian-made Yahont), and of accurate surface to-surface missiles (such as the Iranian-made Fateh-110, bombed twice in the beginning of May).

Suddenly, Israel stopped being afraid of Arab strength and began to be worried about Arab weakness.

The internal chaos in Syria probably helps the Israelis to collect further data on the military situation there, without being noticed. On the other hand, one would assume that the Syrian army’s withdrawal from many parts of the country and the fact it had to deploy its units under pressure have made following them a much more complicated mission. Evidently, the decision to strike three times means that Israel had enough information about the weapon shipments to strike.

But there is probably something else at work here: Generals—and air force and intelligence specifically—tend to emphasize the need for taking immediate advantage of tactical opportunities. So far, Syria has not retaliated for the attacks. However, on Tuesday, May 7, President Assad threatened Israel with “resistance at the Golan border,” and a government newspaper announced that “next time will be different.” Israeli Prime Minister Benjamin Netanyahu would certainly think hard before he approves another air strike, even if the IDF’s brass claims that it is absolutely necessary.

Why has Assad refrained from military action until now? Without admitting any responsibility for the strikes, a senior Israeli defense official explained to me that the government believes the Syrian regime does not have enough space for maneuvering. “If they do act, they will involve us directly in their civil war—a result both of us would like to avoid.” This would mean the destruction of the Syrian air force, Assad’s most effective weapon against the rebels. “I know Assad says he is going to react severely next time, but how many times have you said this to your kids and ended up doing nothing?” remarked the official.

But Assad is not the only actor on his side: Israel should also consider the possibility of either an Iranian or Lebanese response. Hezbollah is deeply involved in the civil war in Syria, and it is assumed that the Shiite organization has sent more than 2,000 of its fighters to help Assad’s loyalists. Iranian Revolutionary Guard units are also present in Syria. (The commander of their “El-Quds” force in Lebanon was mysteriously killed on his way to Syria two months ago.) Israel has used this to strengthen its case against Teheran—blaming the Iranians for spreading unrest across the region. Wouldn’t the Iranians and Hezbollah eventually blame Israel—however falsely—for their mounting casualties in Syria? The Israelis believe that Syria’s allies are too busy helping Assad fight for his survival and wouldn’t spend valuable time on minor friction with the IDF. “Until now, our presumed involvement had been minimal,” one military source said. “The Iranians are otherwise occupied.”

More and more, the civil war in Syria is seen in a broader, regional context, and the American hesitance over the right course of action is looked upon in Jerusalem as a disturbing precedent regarding the country’s long-term strategic challenge, the Iranian nuclear project. Will Iran and Hezbollah decide to retaliate for the latest strikes, defending Syrian honor? Israeli intelligence officials assume the chances are slim. But we should remember that they have discovered in the past that some of their assumptions were much too optimistic for this region.

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