April 12, 2011: Israel has deployed two batteries of its Iron Dome anti-missile system near the Gaza border. One is near the town of Beer Sheva (the largest town in the Negev desert) and another near the coastal city Ashdod (the largest city within range of 122mm rockets fired from Gaza). On April 7th, a 122mm rocket was intercepted near Ashkelon, which is south of Ashdod. This deployment was prompted by an increase in rockets fired from Gaza, and the growing use of longer range (20 kilometers) 122mm rockets. Iron Dome proved that it could work under combat conditions, preventing the longer range, factory made, rockets from landing in populated areas.

This is a big turnaround for this system. Four months ago, the Israeli military revealed that its new Iron Dome anti-rocket system was not meant for defending towns and villages, but military bases. For years, politicians touted Iron Dome as a means of defending civilians living close to rockets fired from Gaza in the south and Lebanon in the north. But it turns out that it takes about 15 seconds for Iron Dome to detect, identify and fire its missiles. But most of the civilian targets currently under fire from Gaza are so close to the border (within 13 kilometers) that the rockets are fired and land in less than 15 seconds. This means that the town of Sderot, the closest Israeli urban area to Gaza, cannot be helped by Iron Dome.

This explains why, after Iron Dome was declared ready for action ten months ago, it was surprisingly placed in storage last year. The air force said they would prefer to save money and put the Iron Dome batteries in storage, to be deployed only for regular tests (and for training) and for an actual emergency (an expected large scale attack on southern or northern Israel.) Politicians demanded that at least one battery be deployed along the Gaza border. But the military sees Hamas and Hezbollah stockpiling larger numbers of longer range rockets. This would enable large numbers of rockets to be fired at military bases. The generals believe it's more important to protect the military forces, who ultimately defend Israel, and that's what Iron Dome will now be used for. Since the military bases are far from the borders, longer range rockets, with longer (than 15 seconds) flight times, would be used. Iron Dome would knock down many of these rockets, as it has already done in tests.

Israel has bought seven batteries of Iron Dome, to be delivered over the next two years. Each battery has radar and control equipment, and four missile launchers. The first battery has been delivered. Each battery costs about $37 million, which includes over fifty missiles.

During tests, the system detected and shot down BM-21 (122mm) and Kassam rockets. The manufacturer, Rafael, was offered a large bonus if they got the system working ahead of schedule. When Iron Dome was first proposed five years ago, it was to take five years (until 2012) to get it operational. In addition to the cash incentive, there's also the rockets still coming out of Gaza, and being stockpiled by Hezbollah in southern Lebanon. But the current low rate of rocket attacks are more of a political and psychological danger, than a real one.

Iron Dome uses two radars to quickly calculate the trajectory of the incoming rocket (Palestinian Kassams from Gaza, or Russian and Iranian designs favored by Hezbollah in Lebanon) and do nothing if the rocket trajectory indicates it is going to land in an uninhabited area. But if the computers predict a rocket coming down in an inhabited area, a $40,000 guided missile is fired to intercept the rocket. This makes the system cost-effective. That's because Hezbollah fired 4,000 rockets in 2006, and Palestinian terrorists in Gaza have fired over six thousand Kassam rockets in the past eight years, and the Israelis know where each of them landed. Over 90 percent of these rockets landed in uninhabited areas, and few of those that did caused few casualties. Still, a thousand interceptor missiles would cost $40 million. But that would save large quantities of military equipment and avoid many dead and injured troops. Israel already has a radar system in place that gives some warning of approaching rockets. Iron Dome will use that system, in addition to another, more specialized radar in southern Israel.

The rocket attacks had been around since 2001, but got much worse once Israel pulled out of Gaza in August of 2005. This was a peace gesture that backfired. From 2001 to 2005, about 700 rockets were fired from Gaza into Israel. Since the 2005 withdrawal, over 3,200 more rockets were fired into Israel. The rate of firings increased after Hamas took control of Gaza in June, 2007.

Hamas has been bringing in more factory made Iranian and Chinese made BM-21 and BM-12 rockets. Israeli intelligence officials believe Hamas currently has, in Gaza, some factory-made BM-21 rockets, each with a range of 20-40 kilometers. They also have some shorter range (six kilometers) , Russian designed B-12 rockets. These are not smuggled in much, because the locally made Kassam II has about the same range. However, the B-12 is more reliable (more reliable trajectory and fuze, so more are likely to land where aimed and explode.)

The B-12 is a 107mm, 19 kg/42 pound, 107mm, 84 cm/33 inch long rocket that is very popular with terrorists. This rocket has a range of about six kilometers and 1.35 kg/three pounds of explosives in its warhead. Normally fired, from a launcher, in salvoes of dozens at a time, when used individually, it is more accurate the closer it is to the target. This 107mm design has been copied by many nations, and is very popular with guerillas and terrorists because of its small size and portability. There is a Chinese BM-12 variant which has a smaller warhead and larger rocket motor. This version is supposed to have a range of about 12 kilometers.

The 122mm BM-21s weigh 68.2 kg/150 pounds and are 2.9 meters/nine feet long. These have 20.5 kg/45 pound warheads, but not much better accuracy than the 107mm model. However, these larger rockets have a maximum range of 20 kilometers. Again, because they are unguided, they are only effective if fired in salvos, or at large targets (like cities, or large military bases or industrial complexes.) There are Egyptian and Chinese variants that have smaller warheads and larger rocket motors, giving them a range of about 40 kilometers.

The rocket attacks from Gaza have been remarkably ineffective, killing only 40 people (half from rockets, the rest by mortars) in eight years. Hamas has had to fire about 270 rockets or mortar shells for each Israel soldier or civilian they have killed. Israeli counterfire killed or wounded a Palestinian for every three Palestinian rockets or mortar shells fired. One Israeli was killed or wounded for every 40 rockets or mortar shells fired. Israeli fire was much more accurate, with most of the Palestinian casualties being terrorists or others involved in building or firing the rockets and mortars. Hamas has tried to get civilians killed, by storing rockets in residential areas, and firing them from those neighborhoods as well. Although Hamas believes in the concept of "involuntary martyrdom" (getting civilians killed for the cause, even if the victims are not willing), many of its chosen candidates are not eager to die. So civilians stay away from areas where the rockets are launched, and try to conceal the fact that rockets are hidden under their homes.

Meanwhile, up north in Lebanon, Hezbollah have stockpiled over 40,000 factory-made rockets, mainly BM-21s brought in from Iran via Syria. This is three times as many rockets as they had in the Summer of 2006, when over 4,000 rockets were fired into northern Israel, killing about fifty people, most of them civilians. Over a thousand Lebanese died from Israeli counterattacks. Hezbollah and Hamas plan to launch a joint rocket attack on Israel eventually. The Israelis have been planning more effective countermeasures, which they have not been discussing openly. There is also the option of installing Iron Dome in the north, but that has not been assured yet.

Meanwhile, the only known weapon that can stop the short range rockets is the American Centurion, a U.S. Navy Phalanx autocannon designed to knock down anti-ship missiles. Centurion has been successful in shooting down mortar shells and short range rockets in Iraq and Afghanistan, but Israel has not bought any yet.