While intelligence assessments consistently paint a grim portrait of thousands of missiles and rockets showering down on Israel's civilian population and infrastructure in the future, the Jewish state unveils its next-generation missile-defense system.

Arrow III, an interceptor designed to knock out ballistic missiles, has until now been shrouded in secrecy. A full-scale model was put on display at the second annual International Aerospace Conference and Exhibition held in Jerusalem on Monday.

In line with the perception that the upgrading of existing systems is a never-ending process in light of changing threats, the engineers who are developing Arrow III have been tasked with achieving a daunting technological feat: creating a booster-rigged kamikaze satellite that will collide with incoming long-range ballistic missiles beyond Earth's atmosphere with pinpoint accuracy.

Like its two older siblings, the development of Arrow III by the state-owned Israel Aerospace Industries (IAI) is being underwritten by the United States. The system is expected to become operational by 2015, according to project director Yoav Turgeman.

Following the aftermath of the 2006 Lebanon war, in which an estimated 4,000 Katyusha rockets and mortars slammed into northern Israel, the country's best and brightest engineers were recruited in a national mission to come up with countermeasures.

Enormous financial resources, including a substantial U.S. investment, were poured into their creation. The bulk of the effort is shouldered by IAI and Rafael Advanced Defense Systems, a division of the Israeli Defense Ministry. A host of smaller local defense contractors supplement the projects.

At the government-sponsored conference, missile defense program directors were each given 15 minutes to update an audience of military and civilian professionals on the progression of leading missile-defense systems.

Some are already operational, while other systems are still under development and slated to be operationally ready in the coming years. The Israeli missile-defense concept presented here on Monday is described as a multi-tier active air defense (MTAD), a network which aims to provide a comprehensive shield against a multitude of threats on several fronts.

At the lowest tier of MTAD is Iron Dome, which intercepts rockets at ranges of 5 to 70 km. Rafael developed the system in record time "about two-and-a-half years from the drawing board to the operational stage," said defense officials.

Israeli Channel 10 TV on Sunday broadcast the first footage of recent live testing of Iron Dome in southern Israel. Israel Air Force crews manning the fire control center burst into cheers as the system succeeded in destroying a salvo of three Grad and two Qassam rockets.

The next tier of the shield is David's Sling, designated to intercept an assortment of more powerful rockets. Developed jointly by Rafael and U.S. missile giant Raytheon, the system is scheduled to become operational by 2013, IAF northern air defense chief Col. Zvika Haimovitch said at Monday's conference.

Officials said the defense network as a whole is expected to be fully operational by 2015. "Within the coming five years, we will see this doctrine implemented, a vision turned into a reality," Haimovitch said.

The defense experts who took the stage also spoke at length about worst-case scenarios that they envision unfolding, a sobering reminder that the present relative calm in Israel's skies could shatter in a moment.

"The firepower in terms of missiles and rockets now available to Israel's enemies is growing," said Uzi Rubin, the founder and first director of the Israel Missile Defense Organization (IMDO) in the Ministry of Defense, estimating that Israeli cities might be hit by upwards of 13,000 missiles and rockets.

Despite the great promise that the new systems hold in minimizing casualties and damage, Monday's speakers, by their own initiative, cautiously noted their limitations.

"I would say 'reasonable protection.' In principle, you can never think of 100 percent protection," said Arieh Herzog, the current director of IMDO.