So why does the Defense Secretary believe an Israeli strike may occur before the start of summer? Let Israeli Defense Minister Ehud Barak, speaking at the World Economic Forum in Davos, Switzerland last Friday, explain:

We are determined to prevent Iran from turning nuclear. It seems to us to be urgent, because the Iranians are deliberately drifting into what we call an immunity zone where practically no surgical operation could block them.

“Immunity zone” is a term coined by Barak to describe the point in time in which Iran has successfully moved enough of its nuclear program deep underground (literally, buried in mountains), rendering an Israeli or even U.S. attack futile. It’s the approach of this “immunity zone” that is propelling Israel toward making a decision to possibly attack Iran’s nuclear reactors while it still can.

Upon returning to Israel this past Monday, Barak reiterated Israel’s position:

We must not waste time on this matter; the Iranians continue to advance (toward nuclear weapons), identifying every crack and squeezing through. Time is urgently running out.

And to put an even finer point on it, here’s Barak before he set off for Davos, speaking at Israel’s annual Herzliya Conference:

If sanctions don’t achieve the desired goal of stopping [Iran’s] military nuclear program, there will be a need to consider taking action. A nuclear Iran will be more complicated to deal with, more dangerous and more costly in blood than if it were stopped today … In other words, he who says in English ‘later’ may find that ‘later is too late.’

If the big question this spring is whether or not Israel is going to attack Iran, the runner-up has to be how Iran would respond. Opinions are varied, ranging from Iran doing nothing to sparking a regional war. Certainly among these possibilities is a conventional ballistic missile attack on either Israel’s nuclear complex in Dimona or population centers like Tel Aviv and Haifa. Indeed, earlier this week, Iran’s semi-official Fars news agency quoted a senior commander of the Islamic Revolutionary Guards Corps as saying that “Any place where enemy offensive operations against the Islamic Republic of Iran originate will be the target.”

So what would such a retaliatory missile attack look like? What are Iran’s ballistic missile capabilities and how much damage might they inflict on Israel? One can’t be entirely precise in assessing the Islamic Republic’s missile program due to a lack of transparency, not to mention outright deception on the part of the Iranians, but there is some meaningful agreement among experts on Iran’s short-and medium-range ballistic missiles (SRBM and MRBM, respectively) if not its prospects for developing intermediate-range or intercontinental ballistic missiles.

According to a report for the United States Institute of Peace by former U.N. weapons inspector Michael Elleman, Iran’s ballistic missile arsenal is the “largest and most diverse” in the Middle East. While Israel is out of range of Iran’s SRBMs, which are defined as ballistic missiles whose range reaches up to 1,000km, Iran does possess at least two types of MBRMs which can theoretically reach every inch of Israel. These include the Ghadr-1 (also known as Shahab-3 Variant), a modified version of the North Korean No-Dong, and the more advanced Sajjil series, which take minutes to prepare rather than hours like the Shahab series and Ghadr-1. There are also a number of missiles whose existence or operability is treated with some skepticism in the West. These include a purported shipment of North Korean BM-25 missiles in 2006, the Iranian-made Fajr-3, and Shahab 4, 5, and 6 missiles.

Open-source assessments of Iran’s MRBM inventory are hard to come by and can be vague and contradictory. According to an April 2010 unclassified report from the Office of the Secretary of Defense (OSD), Iran has “approximately 1,000 missiles that range from 90-1,200 miles.” What proportion of those 1,000 missiles are MRBMs isn’t clear. According to a 2005 Congressional Research Service report, a low-end estimate of Iran’s SRBMs is less than 500. Using the OSD report as a guide and doing a little arithmetic leaves one with the possibility of Iran having perhaps 500 MRBMs. Using the same method, this time with OSD’s high-range estimates of Iran’s SRBMs, leaves Iran’s MRBM stock at fewer than 200. High range estimates by Global Security put Iran’s MRBM arsenal at just over a hundred.

Again, open-source estimates of Iran’s missile inventory are just that – estimates. Nonetheless, it does appear that Iran possesses a not insignificant arsenal of MRBMs with which it can inflict death and destruction upon Israel if it so desires. But quantity, of course, is different from quality, and the Iranians’ MRBMs don’t fare very well in this regard, as they tend to be inaccurate and undependable. Here’s Michael Elleman again:

Iran’s ballistic missiles have poor accuracy. The successful destruction of a single fixed military target, for example, would probably require Iran to use a significant percentage of its missile inventory. Against large military targets, such as an airfield or seaport, Iran could conduct harassment attacks aimed at disrupting operations or damaging fuel-storage depots. But the missiles would probably be unable to shut down critical military activities. The number of transporter-erector-launchers (TELs) available and the delays to reload them would also limit the impact of even a massive attack.

This seems to be the stance Defense Minister Barak is taking. He reportedly played down the risks associated with an Iranian missile attack in an interview with a radio station a number of weeks ago, maintaining that casualties from such an attack would be limited. This mirrors a statement he made last November in which he maintained that Israel would only incur “about 500 civilian casualties.” Elleman agrees with Barak’s assessment:

Without a nuclear warhead … the casualties would probably be low – probably less than a few hundred, even if Iran unleashed its entire ballistic missile arsenal and a majority succeeded in penetrating missile defenses.

If this becomes the prevailing view among Israel’s leadership, then MRBMs alone will not serve as a sufficient Iranian deterrent to a preemptive attack from Israel. But ballistic missiles aren’t the only means by which Iran can retaliate. Israel must also consider a possible barrage of missile attacks from Iranian proxies in Lebanon and Gaza. It is this possibility that I will examine in next week’s column.

*Photo Credit: Wikimedia Common