06/12/2012 12:47 pm ET Updated Aug 12, 2012

Insurrection in Syria: Israel's Ultimate Shield Against Iran?

Co-authored with Mark Donig

As the Syrian uprising forges uneasily ahead, the long shadow of war continues to loom over Israel and Iran. While Tehran's closest ally continues to grapple with its insurrection, Iran's primary proxies, Hamas and Hezbollah, have consequently recalibrated their own strategies over how to respond to the Arab Spring. Yet even as change sweeps the region, analysts still maintain their long-held belief that an Israeli strike on Iranian nuclear facilities would incur a massive retaliation. Iran, so the argument goes, would mobilize Syria, Hamas, and Hezbollah to wreak havoc on the Jewish State. Implicit in this assumption is that the upheaval in Syria has failed to yield a drastic change in Iran's capability to wield power over its friends.

However, in the past year, the conflagration in Syria has depleted Damascus' resources; led Hamas to significantly (if not entirely) shed Iranian patronage; and caused Hezbollah to believe that war with Israel may not be in its long-term interests. Before the Syrian revolt, there was every reason to think that all three would be at Iran's beck and call. Today, such logic may no longer hold.

With revolt embroiling Syria, the Assad regime remains on the ropes. It is running out of money, its military capacity is stretched to the limit, and it has lost the capability to deal with any issue beyond its own borders. Simply put, Syria only has the means to focus on its own survival, and nothing else. Before the Syrian uprising, there was a strong possibility armed conflict between Iran and Israel would have brought Syria into the fold. Today, it is clear that the risk of Syrian involvement in such a scenario is practically null.

Furthermore, the revolt in Syria has driven a wedge between Hamas and Iran that did not previously exist. The two have experienced a severe falling out over Hamas' desertion of its Damascus headquarters and its decision not to support Assad. As punishment for Hamas' turn against Tehran's ally in Damascus, Iran has significantly (if not entirely) cut funding and arms supplies to Gaza. This reprimand, while intended to rein in Hamas, has actually had the opposite effect of reducing Hamas' willingness to carry out Iran's wishes. Such a state of affairs makes it less likely that Hamas would carry out Iran's agenda in the event of war, as doing so would trigger an overwhelming Israeli retaliation in Gaza.

It is in this context that Hamas' leader Ismail Haniyeh recently stated that the group would likely stay on the sidelines in the event of an Iran-Israeli conflagration, announcing that Iran "did not ask anything of us" and "is not in need of us." Before the uprising in Syria, there was no doubt that an Israeli attack on Iran would have incurred hundreds of rockets from Gaza landing on Israeli soil. Today, even with Iran sure to push its proxies following an Israeli strike, Hamas appears to have strong incentives to keep its rockets grounded.

It may then seem fair to estimate that of Iran's allies, Hezbollah in Lebanon would be the most likely to do Tehran's bidding in the outbreak of war -- yet here, too, there are complications. Even had there been no revolution in Syria, the Lebanese people would have little interest in a repeat of Hezbollah's last war with Israel in 2006, which engulfed much of the country and leveled Beirut. Furthermore, Hezbollah has since become the dominant party in Lebanon's cabinet, and thus will be held even more accountable for the damage it incurs upon its own people. Indeed, the fact that the Israeli-Lebanese border has remained relatively quiet since 2006 implies that despite its rhetoric, Hezbollah remains reticent.

Still, deterring Hezbollah further is the fact that as the situation in Syria devolves into chaos, the path of armaments and aid that travels from Tehran to Beirut may soon no longer run through Damascus, if it can still run at all. The fraying of the Shiite crescent means that Hezbollah may not be able to restock its arsenal in the event of conflict with Israel as effectively as it has in the past. Before the Arab Spring hit Syria, Iran could have mobilized Hezbollah into war with Israel nearly at whim. Today, as conventional alliances give way to regional upheaval, there is no guarantee of the extent to which Hezbollah will answer an Iranian call to arms.

With each of Iran's regional proxies and allies hamstrung by the effects of the Syrian insurrection, analysts and pundits may be wise to recalibrate their assessment of the risks Israel faces in the wake of an attack on Iran. Surely, Iran would strike back against Israel in the event of an attack. Furthermore, the fact that Iran's capabilities may be more constrained does not mean that a pre-emptive strike, which would be extremely challenging to execute and could politically strengthen Tehran, is a prudent option for Israel. Yet with turmoil across Syria forcing the hand of Iran's proxies and allies, the question must be asked: Does Iran still possess the capability to respond against Israel with severity and consequence? Before upheaval struck Tehran's closest friend, the answer appeared obvious. Over one year into the Syrian uprising, that may no longer be the case.

Gabriel Kohan is a former Israel Government Fellow and Mark Donig is a former Dean's Fellow at the Lauder School of Government's Program for the Diplomatic Corps at the Interdisciplinary Center in Herzliya, Israel.