The preliminary, preoperational deployment of two Iron Dome batteries represents a new dynamic in the recent exchanges of fire between the Israelis and Hamas and other Palestinian militant groups in the Gaza Strip. One battery is deployed outside Bersheeba, the other outside Ashkelon; they are intended to defend against artillery rocket fire in the 4- to 70-kilometer range, beneath the range of a parallel system in development for longer-range rockets and Israel's already-deployed ballistic missile defenses. The Israeli government has been making promises regarding Iron Dome for years. Even this preliminary deployment of a new technology has not been without its delays, cost overruns and hurdles, and it will be many years before even the current configuration envisioned is fully deployed. Nevertheless, weapons have political significance beyond their actual effectiveness, and in this case, both provide important context for understanding the current and evolving significance of Iron Dome.

Short vs. Long Term

Even after being subjected to thorough testing and evaluation before deployment, any new weapon will be confronted with operational realities and unforeseen complications when actually used. No weapon system is designed to perfection, and even optimal or anticipated performance is generally unlikely at the outset — particularly when a system is rushed onto the battlefield. However, these battlefield experiences allow engineers to refine and strengthen their design. In the short term, there is also the significance of the political perceptions of the weapon system. In the run-up to the 1991 Gulf War, an early version of the U.S. MIM-104 Patriot was deployed to Israel to provide ballistic missile defense. Though it performed dismally during this deployment, initial incorrect reports of successes helped keep Israel out of the war (and later variants would show significant improvements). The psychological impact of the deployment of a new, high-end American weapon system thus achieved a political end. Israel is in the process of talking up the initial deployment of Iron Dome and has published pictures of successful intercepts. Just as in the Gulf War, popular perceptions of the system's effectiveness can be as important as its actual effectiveness. The conflict already has helped speed the procurement and fielding of additional batteries and secured additional funding from the Americans. Hamas, on the other hand, has denigrated Iron Dome's effectiveness and mocked the cost disparity between its own weapons and Israel's defenses. In practical terms, offensive rockets inherently tend to be cheaper than the more sophisticated interceptors required to defend against them. This is certainly the case in Gaza, where homemade Qassams can cost just a few hundred dollars to assemble in a garage. By contrast, a single Tamir interceptor with which Iron Dome fire units are armed currently costs at least $25,000, with some estimates running as high as $50,000. This makes for a dynamic in which volume fires of far cheaper rockets can overwhelm defensive batteries' magazines. Any attempt to do so, however, would be a radical departure from how Hamas or even Hezbollah have employed artillery rockets in the past. Both groups instead have sought to conserve ammunition and get the most impact out of individual and small salvos of rockets. (click here to enlarge image) The countertactic/counter-countertactic dynamic is a reality of warfare in any ongoing struggle. Thus, while little suggests Hamas has adjusted its tactics yet, it can be expected to make such adjustments, even to the weapons at its disposal, as Iron Dome and other Israeli defensive systems are refined and become more effective. In addition, the inherent inaccuracy of Palestinian militant groups' unguided rockets (particularly the Qassams) means that many fall ineffectively in uninhabited territory. Iron Dome has a discerning fire-control system; it will only attempt an intercept if the rocket is set to fall within a pre-defined area, meaning not every round fired from Gaza will reduce the Israeli stockpile of expensive interceptors. Of course, how accurately Iron Dome's fire control is able to plot potential impacts and how many targets it can track and plot at once — in other words, the system's threshold for being overwhelmed — are important questions.

Potential Consequences

No defensive system is perfect, but as with any countertactic, if it proves successful, it may eventually force an adversary to alter its behavior. If Iron Dome does this, it could force more rockets from Gaza to be fired in larger salvos, complicating militants' ability to keep their arsenals dispersed and their ability to quickly emplace and displace — to "shoot and scoot" to avoid detection during preparation for firing and counterbattery fire and other responses from the Israelis. It could also force militants to expend their arsenals more quickly, increasing the logistical intensity of smuggling operations and therefore their vulnerability to detection. On the other hand, the prospect of the erosion of the effectiveness of Hamas' weapons — which would be based less on Iron Dome's actual effectiveness than it would on Hamas' perception of such — could create a use-it-or-lose-it incentive for Hamas. Israel has a separate problem, since its domestic imperative to defend itself could force it to act aggressively with repercussions far beyond Gaza. If Hamas can goad the Israelis into acting aggressively here, it could quickly and radically undermine the Israelis' position regionally. Improved defenses would give Israel some additional control in a crisis and increase its ability to escalate and de-escalate — something now largely controlled by the aggressiveness of Hamas in its rocket and mortar fire. Hamas fears continued isolation by an Israeli blockade supported by an Egyptian regime in Cairo, a fundamental, long-term problem for the movement. However, Israel fears the commitment of the current Egyptian regime to that blockade, so Hamas' current escalation dominance gives it leverage over Israel, at least for now. However, the prospect of that continued isolation combined with the prospect in the long run of an even moderately effective defense against its biggest and longest-range rockets — its best remaining weapon to hit at Israel — must be a matter of concern for Hamas even if it remains years from fruition in the best of circumstances. Ultimately, Iron Dome is only part of the long-term problem for Hamas. Various counter-rocket, artillery and mortar systems are in development or in the field. Iron Dome currently fills a unique envelope, but it is but one element in a multilayered approach already in progress in Israel. Meanwhile, the weaponization of lasers for just this type of role is also rapidly advancing, for the first time creating a realistic prospect of operationally mature and deployable weapons, and decades of work in ballistic-missile defense is now trickling down into smaller packaging and smaller, shorter-range threats. It may take Israel up to five years just to deploy ten batteries — and reports have suggested between a dozen and 20 batteries would be required to provide full coverage of Gaza alone — so Iron Dome's success is far from assured. With or without Iron Dome, however, Israel will increasingly be able to use new weapons technologies to undermine and degrade the effectiveness of Hamas' core tactic of striking at Israel with crude ballistic weapons.