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Israel has put together a multilayered shield designed to intercept rockets and missiles capable of striking it from as close as the Gaza Strip and as far away as Iran, reflecting concern that future conflicts will target Israel's civilian population centers.

At this sprawling air base in central Israel, soldiers in a fortified control room are training to activate a cornerstone of this shield — the Arrow missile defense system, meant to protect Israel from its enemy Iran's expanding array of missiles.

The Arrow, produced jointly by state-run Israel Aerospace Industries Ltd. and Chicago-based Boeing Co. at a cost of more than $1 billion, is being deployed in Israel after successful tests in both Israel and the U.S. It has not been tested in combat, but the system is already in its third generation, having been fine-tuned to deal with increasingly complicated threats.

The Arrow was designed to counter Iran's Shahab ballistic missile, which is capable of carrying a nuclear warhead and whose range of 1,250 miles (2,000 kilometers), puts Israel well within striking distance. Despite Iranian denials, Israel is convinced Iran is developing nuclear weapons.

Threats also come from much closer to Israel.

In 2006, Israel fought a fierce monthlong war with Hezbollah guerrillas in Lebanon, when Hezbollah fired nearly 4,000 rockets at Israel. That pointed up two stark facts: Israel had no tool to knock them down — neither did anyone else — and Israel's civilian population, concentrated mostly along the nation's Mediterranean coast, was increasingly vulnerable to attack.

In response, Israel has developed additional systems: "Magic Wand," aimed at stopping intermediate-range missiles, and the "Iron Dome," which shoots down rockets fired from short distances of just a few miles (kilometers) from the Gaza Strip and Lebanon.

Last month, Israel successfully introduced the Iron Dome and shot down several Palestinian-fired rockets from Gaza. Palestinian militants have fired thousands of crude, short-range weapons at Israel in recent years, and up to then the military had no answer except airstrikes after the fact.

The Arrow, first deployed in 2000, was the first brick in what Israel hopes will be a wall of protection against incoming rockets and missiles.

The Israel military on Thursday allowed foreign journalists to observe the Arrow missile defense control room at the Palmachim air base.

Entry is through a set of 3-inch-thick steel doors. The control center is reinforced against nuclear attack, a military official indicated.

An aerial map of the Middle East appears on each of a dozen screens around the room, where soldiers "intercept according to the type of threat," said an officer identified only as Lt. Col. O, according to military regulations.

Soldiers are trained to cope with situations where as many as hundreds of rockets are fired simultaneously, said Maj. Tal Mast, a former Arrow commander who has spent 13 years in air defense and still trains twice a month as a reservist.

After detecting an incoming missile, soldiers have minutes at best and seconds at worst to assess what type of projectile it is, calculate its trajectory and decide whether it needs to be shot down or whether it might land in an open field or the sea, making interception unnecessary.

The computer system helps make the decisions.

An "X'' on the screen designates an incoming missile as "irrelevant" — meaning it is not expected to hit anything and need not be shot down.

If the decision is to fire, a missile is dispatched from a transportable, trailer-mounted Arrow launcher with six missile tubes that can be reloaded in 15 to 20 minutes, officials said.

At one point in a drill, the screen showed two Scud missiles, designated by yellow triangles, homing in on central Israel from Lebanon, and two others from Syria. A blinking blue triangle, signifying the Arrow's interceptor missile, homes in on one of the incoming missiles. Their paths cross, and both disappear from the screen. The other missiles, deemed nonthreatening, are allowed to continue on their course.

In real life, the "fire" button is a simple F2 stroke on the computer keyboard, Lt. Col. O said.