Shortly before sunset on March 9, 2012, Palestinian rocket squads in the Gaza Strip fired four Grad-type Katyusha missiles at the southern Israeli communities of Ashdod, Gan Yavne and Kiryat Malachi.

The launches were immediately detected by specially modified Elta multi-mission radars attached to antimissile batteries in Ashdod and Ashkelon. Within sixty seconds, each of the incoming rockets had been neutralized. Over the next nine days, Israel’s three operational Iron Dome batteries destroyed another fifty-two of seventy incoming Qassam and Katyusha rockets threatening populated areas near Be'er Sheva, Ashkelon and Ashdod.

The system’s remarkable 76 percent intercept rate did not go unnoticed in Washington. Building on a $205 million contribution in funding for the project in fiscal year 2011, bipartisan legislation introduced in Congress on March 21 authorizes the Obama administration to release additional unspecified funds, upon request by the Israeli government, for the “procurement, maintenance and sustainment“ of Iron Dome batteries.

Within a week of the bill’s introduction, Pentagon officials announced plans to ask Congress for “an appropriate level of funding” to support the acquisition of additional Iron Dome systems based on Israeli requirements and production capacity (estimated at approximately four batteries per year). Though details of the grant-funding package have not yet been determined, U.S. and Israeli sources estimate that the request could exceed $500 million to cover production of up to ten batteries, each with a protective footprint that can cover a city twice the size of Haifa (24.6 sq miles).

Talks with the United States on a new round of missile-defense funding should be completed by July 2012, at which point a decision will be made on whether to support full deployment or scale back expectations in a climate of fiscal restraint. Anticipating the need to make do with fewer units, planned advances are expected to eventually increase Iron Dome’s intercept range from approximately forty-five miles to 155 miles, providing sufficient operational flexibility to defend the northern and southern borders from as far away as the greater Tel Aviv area.

With three systems currently deployed in the south, a fourth in the final stages of acceptance testing near Tel Aviv and three more units on order, the additional commitment of between six and ten batteries should be able to provide full, if not hermetic, coverage of threatened Israeli population centers by 2014. The implications of this development carry the potential to change the nature of strategic decision making in the region.

Effective deployment of a short-range missile-defense system deprives militants of a lethal tool of coercive diplomacy while simultaneously granting Israel’s political leadership flexibility to react strategically to enemy rocket fire, free from domestic pressure to launch controversial “crushing-blow” reprisals. A problematic dependence on major military mobilizations and disproportionate retaliation can instead be replaced with a smarter, integrated approach that matches combined-attack operations (preemption, prevention and retaliation) with both passive and active missile defense (shelters and intercept systems). When properly coordinated in the early stages of conflict, this approach can act as a force multiplier, employing Iron Dome missile-defense systems to neutralize the threat from short-range rockets and freeing air force resources to focus on enemy strategic facilities and militant launch squads.

Comprehensive deployment of the Iron Dome system should also meet the objective of strategic deterrence. If potential aggressors know that a missile launch will invite a military response and international sanction while failing to achieve any operational or strategic objective, they may be discouraged from using the weapon in the first place. This has broad implications for Israeli disengagement strategy in the West Bank, where the threat posed by short-range rockets has been cited by Israeli leadership as justification for an indefinite military presence along the Jordan Valley.

The most common argument offered against a doctrinal shift to embrace active missile defense originates with senior members of the Israeli Defense Forces for whom a traditionally offensive force posture is considered fundamentally important to the myth of Israeli invincibility. On this basis, many senior defense-establishment figures oppose prioritizing funds for missile defense over new attack squadrons within the procurement budget of the Israeli Air Force.

American support for the expansion of Iron Dome goes some way toward alleviating this concern, but the shield’s success rate is high enough on its own to validate the economic rationale of the project. At an interceptor unit cost of between $25,000 and $60,000, the seventy-four attempted rocket interceptions in the Gaza conflict ran between $1.8 and $4.5 million, a negligible percentage of Israel’s annual $16.3 billion defense budget and a small price to pay to avoid the loss of life, capital and productivity that can accompany a rocket war on the southern front. The domestic R & D pedigree of Iron Dome also opens the door to profitable exports that can reduce costs, either by way of foreign-development financing or overseas sales.

Because no system has yet been devised that can provide a hermetic security guarantee, militant groups in Gaza are likely to be studying Iron Dome for flaws that might be exploited. New tactics may include aiming more frequently at areas beyond the shield’s current range and employing cluster-launch vehicles to overwhelm the system’s current capabilities. But Iron Dome is also expected to improve as combat lessons are incorporated and new batteries deployed across the country. Already, the system’s performance in March 2012 has silenced many of its most devoted detractors.

Israel’s allies and enemies are being challenged to accept a strategic shift to the regional-security dilemma that has kept the country’s border communities on edge for the past decade. A new age of active missile defense has begun.

Ian Siperco is head of research for a security-focused international political-risk consulting firm.

Image: Israel Defense Forces