Writing at Geostrategy Direct (subscription required), Bill Gertz reports that Israel’s General Staff is weighing the possibility of a multi-front war against Iran and Syria.

Sources tell Gertz that IDF leaders have ordered feasibility studies on a potential, simultaneous strike against its two most powerful adversaries. Officials say the planning is based on Israeli intelligence assessments that the U.S. will not confront Damascus or Tehran, regardless of the threat they pose.

We contemplated this scenario almost two years ago, suggesting that Israel might face a conflict with not only Iran and Syria, but with Hizballah and Hamas as well. Similar predictions were offered by Joshua Muravchik, a resident scholar at the American Enterprise Institute and former U.N. Ambassador John Bolton.

At the time, we suggested that the IDF was already at work on planning for a multi-front war, for rather obvious reasons. Israel has been surrounded by enemies throughout its existence, and fought multiple foes in four wars of national survival: 1948, 1956, 1967 and 1973. While some of the enemies have changed (with Hamas and Hizballah replacing Egypt), the strategic challenge remains relatively unchanged.

So, how would Israel prosecute a simultaneous war with its terrorist foes, along with Iran and Syria? In the summer of 2007, we outlined a fight/hold/swing strategy, akin to U.S. plans for concurrent regional conflicts in the Middle East and Far East.

Interestingly, the IDF has already taken the first step in that process. The recent war with Hamas has severely crippled the terrorist group, leaving it with a diminished capacity to launch rockets into Israeli territory. Two years ago, some analysts believed that Israeli forces would simply seal off the West Bank and Gaza, believing that the threat from Hamas could be contained.

Obviously, the escalating number of rocket and missile attacks from Gaza forced a change in the IDF strategy. But the wider consequences of the three-week war are not lost on Israeli planners. By taking on Hamas last year, the IDF simplified planning for a multi-front war, at least over the near term.

While the challenge of fighting three adversaries–at the same time–is daunting, we believe the Israelis could pull it off, though it would place a severe strain on logistics, communications and command-and-control resources. In terms of operational priorities, the IDF would place its initial focus on Iran:

[As a first step] the Israeli Air Force would launch its long-predicted strike against Iran, aimed at disabling that country’s nuclear and long-range missile programs. Surprise is of the essence, and an early attack against Tehran would reduce that potential threat–before enemy air defenses go on heightened alert, and before the IDF become pre-occupied with operations over Lebanon and Syria.

Given the distance and routing considerations associated with the raid, the strike on Iran would (most likely) be a one-time shot. The Israelis understand that Tehran’s retaliatory options are limited to attacks by proxies, and long-range strikes, using its relatively small arsenal of Shahab-3 missiles (the longer-range BM-25 is not believed operational at this time). Israel would employ the Arrow II ballistic missile defense system to counter MRBM attacks, and its own Jericho II missiles–capable of carrying nuclear warheads–for retaliatory strikes, as required.

With the Iranian threat reduced, the Israelis would quickly shift their focus to the Golan Heights and Lebanon. Syria’s air force and air defenses could be neutralized rather quickly, giving the Israelis complete control of the skies, and support for a ground assault past the Golan. The IDF has no intention of occupying Damascus, just creating more strategic depth and eliminating forward bases for Syria’s FROG-7 rocket force.

Additionally, IAF jets would also pound Syrian airfields that can accommodate cargo aircraft, to prevent aerial resupply from Iran, and trans-shipment to Hizballah. Syrian forces would provide determined resistance on the ground, but they are no match for the IDF. Damascus would also attempt to saturate Israel with missile and rocket attacks, but an IDF advance into Syrian territory would negate that threat, as would air dominance by the IAF.

Syrian FROGS and SS-21 missiles are capable of carrying chemical warheads, but Damascus understands that a WMD strike on Israel would invite their own nuclear annihilation. Israel also has another advantage in the expected “missile war” with Syria–the availability of Patriot missile batteries, capable of handling the FROGs and SS-21s, leaving the Arrow II to battle Iran’s MRBMs.

As the situation in Syria stabilizes, the IDF would shift its attention to Hizballah and Lebanon. As with Hamas in the south, Hizballah’s attack options are limited. However, the success of their rocket attacks against Israel last summer makes it imperative for the IDF to deal with this threat, through a combination of airpower and a ground incursion. As with the Golan operation, the Israelis have no plan for a deep push into Lebanon; instead, they would focus on pushing Hizballah gunners out of range, and disrupting their supply lines into Syria.

In terms of timing and tempo, it would be virtually impossible to distinguish the various stages of the conflict. As the Israeli Air Force strike package heads for Iran, other aircraft would launch attacks on key targets in Syria, while missile defenses prepare for enemy attacks. As with past Israeli strikes, the campaign would be masked by denial and deception efforts, aimed at securing operational and tactical surprise.

Will this multiple-front war actually unfold in the coming months? Two years ago, some experts believed that such a conflict was imminent. Clearly, those predictions were wrong, for a couple of reasons. First, the IDF needed time to internalize lessons learned from the 2006 Lebanon conflict and prevent similar mistakes in future military campaigns. While the recent “Gaza War” was different than the Lebanon campaign, it’s clear that the IDF did not repeat mistakes of two years ago in going after Hamas.

Secondly, Israel understood that Iran (in 2007) was still years away from obtaining a nuclear weapon. That gave Israeli leaders more time to contemplate their options and plan for potential military options. It’s also worth remembering that the U.S. pressured Israel to give other mechanisms–namely diplomacy–a chance to work.

In the spring of 2009, those alternatives are largely exhausted, though the Obama Administration still wants to talk with Tehran. A senior IDF general recently said that Iran has “mastered the technology” for producing nuclear weapons. U.S. officials disagree with that analysis, while admitting that Iran has enough fissile material for a bomb.

Put another way, Israel’s window for potential action is closing rapidly. Meanwhile, Iran, Syria and Hizballah are continuously expanding their rocket and missile arsenals that are aimed at Tel Aviv, Jerusalem and other Israeli population centers.

We’re guessing that the “studies” ordered by the IDF are merely updates of previous planning documents and intelligence assessments, with a very short suspense date. Israel’s new government has only a limited time to set policy for its most pressing threats.