The Green Pine radar system picks up the Shihab 3 missile six minutes after it is launched from Iran. With another four minutes to spare, sirens go off across the country warning the public to run into shelters, while the Arrow anti-ballistic missile launches from the Palmahim Air Force base just north of Ashdod. Reaching speeds of up to Mach 7, the Israeli missile intercepts the Shihab outside the stratosphere less than 60 seconds after its take-off, thus preventing a large disaster. This is Israel's nightmare: An Iranian-fired missile, possibly carrying a nuclear or other non-conventional warhead. While the IDF Home Front Command is geared up to deal with the aftermath of such an event, most senior officers are counting on the Arrow to prevent it. The day might not be far away. With Military Intelligence predicting that diplomatic efforts to stop Teheran's race for the bomb will ultimately fail, some analysts believe that only a military strike will succeed in halting - or at least stalling - the Iranian nuclear program. According to these analysts, if Iran's nuclear installations were bombed, Teheran would respond by firing long-range Shihab missiles at Israel, even if the IDF were not behind the strike. Israel, however, does not plan to wait for anyone else to act on Iran. As Defense Minister Shaul Mofaz repeated this week: "We will know how to defend ourselves." After the successful launching of the new Eros B Israeli spy satellite on Tuesday that will follow developments at Iran's nuclear installations, Mofaz said again: "Above all, we can only count on ourselves." AS THE only operational anti-missile defense system in the world today, the Arrow is the pride and joy of its manufacturers at the Israel Aircraft Industries and its operators in the IAF. On a special visit to the Arrow's secret launch site at Palmahim, The Jerusalem Post was allowed rare access to the missile defense system's command center, Citron Tree, located in a fortified underground bunker manned with soldiers huddled around large plasma radar screens. According to commanding officer Maj. Elyakim, these soldiers use the specially developed Green Pine radar system, which has the ability to pick up and track the signal of incoming missiles fired from Syria and Iran. Once the radar, situated in an igloo-like building next to the command center, detects such a signal, the Arrow begins an automatic launch sequence, unless it receives override orders. "The radar can tell us where the missile was launched from and where it will land," Elyakim explained. "As a result, we also then have the ability to send fighter jets to destroy the enemy missile launcher." The tension in the region, particularly on the Iranian front, has not escaped the Arrow command center, which recently raised its level of vigilance and reinforced its personnel. According to high-ranking officers, the Arrow has the ability to intercept all types of Iranian missiles, including the Shihab 3, even if it is carrying a non-conventional warhead. The Arrow 2 was last tested in December and succeeded in intercepting an incoming rocket simulating an Iranian Shihab 3 at an altitude higher than tested in all of the previous exercises. The system, Elyakim said, is also capable of firing several Arrow anti-missile missiles at once, to intercept a number of incoming enemy missiles simultaneously. AT PALMAHIM, the arrow batteries sit in an upright, 90-degree position. Each launcher holds six missiles and is stationed on a flat-bed truck with wheels, to enable the missile system to be moved to other parts of the country when necessary. The Arrow command center, Elyakim said, works closely with Military Intelligence which is responsible for providing the missile-defense operators with crucial information. "On our own, we can't tell what type of warhead the missile is carrying and whether it is conventional or non-conventional," Elyakim said. In addition, he revealed, so far, the Arrow does not protect all of Israel. The battery in Palmahim covers the center of the country, and the one in Ein Shemer near Hadera covers the northern region. Other areas - mainly in the south - are partly covered. As a result, if an enemy missile is set to land in the middle of an unpopulated area in the Negev, the command center might receive orders not to intercept it with the Arrow - valued at $3.2 million per projectile. The long-term plans, Elyakim said, are to deploy batteries throughout the country, to create a protective umbrella across its skies. In the meantime, he explained, the missile defense system is continuously being upgraded - as were the Arrows at Palmahim - to meet the technological progress of the enemy. "The missile undergoes frequent improvements to meet the developments our enemies make with their surface-to-surface missiles," he said, adding that the improvements are sometimes based on general technological developments in the missile field, and sometimes on intelligence collected on enemy missile advancements. THE ARROW project was established about 12 years ago to address the threat posed by the relatively crude Scud missiles, like the ones Iraq fired into Israel during the first Gulf War in 1991. But as the project developed, the defense establishment was determined not to focus on past wars, but to look ahead to future threats, including faster rockets launched from farther away, possibly with multiple warheads. Nearly $2.5 billion has already been invested in the missile defense system, with two-thirds of the funding coming from the US Missile Defense Agency. While the Arrow is Israel's first line of defense against Iranian missiles, air force Patriot batteries - used during the first Gulf War - serve as the country's backup interception system against incoming missiles. The Arrow missile defense system is also exactly the type of technology a committee led by former justice minister Dan Meridor recommended this week that the defense establishment continue investing in. The committee made history when it presented a report to Mofaz on Sunday containing an officially formulated military doctrine for the state. According to the 250-page report, whose recommendations will mostly remain top-secret, Israel is currently facing a number of major and rapidly approaching strategic-technological threats. The report, authored by Meridor and a committee made up of former and current top defense officials, recommended that the IDF focus its resources on combating the threat of non-conventional weapons and terrorism - referred to by the committee as "super-conventional warfare." "In the past, Israel faced conventional war with its Arab neighbors," Meridor told the Post.s "Now the threats are different, and we are facing non-conventional weapons and terrorism. The idea is to stay ahead in those areas while continuing to maintain an advantage when it comes to conventional warfare as well." The Arrow is relevant to many parts of the report, particularly those dedicated to predictions about other Muslim countries in the Middle East trying to emulate Iran in developing and arming themselves with nuclear weapons. If that happens, the Arrow might just be the thin line separating Israel from existence and obliteration.