Why Iron Dome Can't Be Scaled-Up
Iron Dome is all the rage. It has achieved other-worldly status in some defense circles due to reports that the system intercepted 80 to 90 percent of the rockets launched by Hamas it targeted during the most recent Gaza conflict. One Israeli official went so far as to claim that “Iron Dome is capable of 100 percent [across the board].” India and Korea have expressed interest in acquiring the system. And some observers have argued that the success of Iron Dome vindicates the ongoing and costly U.S. effort to protect Europe and the U.S. homeland from a nuclear-armed missile attack.
Everyone needs to take a deep breath.
Iron Dome has been successful in shooting down unsophisticated, inaccurate, and slow-moving short-range rockets headed for Israel. It also may have reduced the pressure felt by Israel’s leaders to invade Gaza. As far as investments in rocket and missile defense are concerned, you could do far worse than Iron Dome. But as others have already written, Iron Dome is not a solution to the strategic dilemma that confronts Israel in the occupied territories. Hamas’s goal in firing rockets does not appear to be to inflict large numbers of casualties or degrade Israel’s military capability; rather its objectives are more political and psychological in nature.
Over half of the approximately 1,500 rockets fired by Hamas in the recent conflict landed in open areas and were not engaged by Iron Dome. Were Hamas in possession of more accurate missiles, it’s fair to ask whether the system would have been able to sustain such a lofty success rate. The number, accuracy, and speed of the incoming missiles are an important question when thinking about the potential capabilities of Israeli missile and rocket defenses in a conflict with Hezbollah and/or Iran, both of whom possess a much larger number of and more advanced rockets and ballistic missiles. Iron Dome is only equipped to handle rockets with ranges of 5 to 70 km; it can’t handle the faster rockets that fly outside this range.
In an attempt to defend against a wider variety of missile threats, Israel has developed and is developing a number of other defense systems. The David’s Sling system, which reportedly scored its first intercept in a test in late November, is designed to intercept rockets and short-range ballistic missiles with a range of 70 to 300 km. It is expected to be operational by 2015.
In addition, Israel has worked with the U.S. to develop the Arrow missile defense system to counter longer-range ballistic missiles launched from Iran. The Arrow-2 interceptor is already deployed and is designed to intercept targets during the latter stages of their flight. The newest version of the Arrow family, the Arrow-3, is designed to intercept Iranian medium-range ballistic missiles outside the atmosphere in the vacuum of space. The interceptor is still under development and has yet to undergo a flight intercept test.
A full-scale conflict with Hezbollah and/or Iran would present far greater challenges than those posed by Hamas. For example, Hezbollah is believed to possess as many as 40,000 rockets and missiles, meaning it could likely quickly overwhelm Israel’s defense systems. The reality is that any defense system can be overwhelmed by suffient numbers of offensive missiles. Hamas has yet to demonstrate such a capability because its resources are so limited.
Furthermore, many of the missiles possessed by Hezbollah and Iran are faster and more accurate than Hamas’s rockets. Not only has Israel never had to manage a sophisticated battle with hundreds of incoming missiles with different ranges, but in a conflict Hezbollah and/or Iran would likely target Israel’s defenses in an effort to neutralize them. Longer-range Iranian missiles could also carry decoys and countermeasures designed to fool defense systems such as Arrow-3 that operate in the vacuum of space, an intractable problem to which there is still no solution.
The moral of the story, then, is that while Iron Dome has been effective in intercepting limited numbers of short-range rockets fired from the Gaza Strip, its success is not easily translatable to a larger engagement with Iran and/or Hezbollah—to say nothing about the qualitatively different obstacles posed by defending Europe or the U.S. homeland from nuclear-armed missiles. After all, an impressive interception rate of 90 percent is far less impressive if the surviving 10 percent are armed with nuclear warheards.