The newest battery of Israel's stunningly effective Iron Dome missile defence system had been in place in Tel Aviv for just a few hours when militants in the Gaza Strip launched the first long-range rocket that threatened to slam into the densely populated coastal city.
Had the Nov. 17 strike succeeded, Israel's latest clash with Palestinian fighters, then in its fourth day, could have easily devolved into a protracted and devastating ground war. Instead, Tel Aviv residents, who hadn't seriously contemplated the risk of missile attacks on the city since the 1991 Persian Gulf War, marveled as a radar-guided munition soared into the sky and blasted the rocket in a thundering boom.
The interception of the Iranian-funded Fajr-5 rocket — and more than 400 other rockets — played a key role in the truce reached the following week, gave Israel bragging rights for sticking with a defense system that faced sharp domestic criticism, and is all but certain to redefine how the Jewish state and its adversaries fight in the future. For now, Iron Dome, the highest-profile component of Israel's multi-layered missile defense system, has exceeded expectations and is widely seen as a technological breakthrough.
"It was really a miracle," said Zvika Haimovich, the Israeli air force colonel who runs the system, noting that the battery that destroyed the Fajr-5 had been deployed to Tel Aviv only the day before. "It was an amazing process."
Iron Dome is arguably the only undisputed victor of Israel's latest siege on Gaza militants, which left much of the Mediterranean enclave in ruins but has boosted the standing of the militant groups based there. U.S. Defense Secretary Leon Panetta was all praise as he hosted outgoing Israeli Defense Minister Ehud Barak at the Pentagon last week.
"Iron Dome performed, I think it's fair to say, remarkably well during the recent escalation," Panetta said. After noting that the United States has helped finance the system, he added: "Iron Dome does not start wars. It helps prevent wars."
The system's prodigy status today belies its controversial origins.
The threat of rocket attacks has loomed large in Israel for more than a decade. The country's outgunned neighboring adversaries — Hamas, the Islamist group that runs the Gaza Strip, and Hezbollah, the Lebanese militia — began firing rockets at Israel the last decade, putting millions of Israeli civilians in the line of fire.
During Israel's war with Lebanon in 2006, Hezbollah militants fired about 4,000 rockets, killing 44 Israelis and temporarily displacing thousands. Gaza-based militant groups have fired thousands of rockets at populated areas in southern Israel since 2002, a military campaign that the territory's leaders have embraced as an alternative to negotiations toward a two-state solution.
Under intense domestic pressure to stop the rocket attacks, Israel's Defense Ministry began developing Iron Dome in 2007. Skeptics in Israel and Washington abounded, said Uzi Rubin, who ran Israel's missile defense system during the 1990s. Israelis who lived through the 1991 Gulf War recalled the failings of the Patriot missile defense system, which could not stop Iraqi Scud missiles.
"This was weighing heavily on the psyche of decision-makers and the general public," Rubin said in an interview. Shooting down missiles in the sky, he added, seemed like "finding a needle in a haystack. They didn't believe it was going to work."
Officials at the Pentagon originally favored a cheaper, laser-based alternative proposed by U.S. defense contractor Northrop Grumman. The Israeli backers of Iron Dome, which was developed by Israeli defense company Rafael Advanced Defense Systems, ran into political turbulence at home as questions about the cost and effectiveness of the system nearly derailed the project. Each interception costs $50,000 to $100,000.
Despite misgivings in Washington, the Obama administration got Congress to provide $205 million for Iron Dome in 2010, a financial boost that saved the project. The following year, in April 2011, Iron Dome intercepted a Grad rocket fired from Gaza, marking the first such counter-strike on a short-range artillery attack in the area.
When Israel assassinated Ahmed Jabari, the head of Hamas's military faction, in a Nov. 14 airstrike, the country's military anticipated retaliatory attacks. Israeli officials suspected that Hamas and Islamic Jihad, another militant group in Gaza, had stockpiled thousands of rockets since a three-week conflict with Israel in 2008-2009. This time, Israelis feared, Hamas would retaliate with long-range rockets designed and funded by Iran that were capable of reaching Israel's two largest cities, Tel Aviv and Jerusalem.
"They came with improved skills," Haimovich, the Israeli colonel, said. "We could see that in the longer distance from Gaza and more volleys in the south."
Over the course of the recent week-long operation, Israeli officials said, they shot down nearly 85 percent of the roughly 400 rockets fired from Gaza that would have otherwise landed in populated areas. Militants lobbed more than 1,500 rockets during the conflict, according to the Israeli military.
Iron Dome's accuracy rate kept Israeli casualties relatively low: Six Israelis, including two soldiers, were killed in rocket strikes. Perhaps more importantly, said Natan Sachs, an Israel expert at the Brookings Institution's Saban Center for Middle East Policy, it provided the Israeli government with significant political maneuvering room.
"It gave the population a sense that there is an active defense," he said. "Psychologically, that's a very powerful tool."
When Tel Aviv's warning sirens wailed for the first time, Ossie Ravid, an American Israeli lawyer, had a brief bout of panic as she contemplated her options inside a luxury apartment on the 24th floor of a high-rise. Subsequent rocket attacks gave her a front-row view of Iron Dome at work.
"By the third siren, I wasn't scared at all, just fascinated by it," Ravid said. "It was all surreal, the notion that rockets were being fired towards me and that I wasn't really in danger."
Israel and Gaza militants reached an Egyptian-brokered cease-fire deal Nov. 21, a week after Jabari's assassination. Both sides proclaimed victory.
Israel hailed the effectiveness of the Iron Dome, saying the volleys of rockets fired by Palestinian militants would have otherwise put enormous pressure on Prime Minister Benjamin Netanyahu to deploy ground troops in Gaza. Militants in Gaza, meanwhile, asserted that it was their military prowess that staved off a ground invasion. One thing is not in dispute, said Rubin, the former defense official: As the two sides contemplate a future confrontation, Iron Dome will be at the heart of their planning.
"This probably left them scratching their heads," Rubin said, referring to Palestinian militants. "I'm sure their people are sitting down in their labs and thinking about how they will defeat the Iron Dome."
Israel, meanwhile, is planning to vastly expand its missile defense network. In coming years, military officials say, they expect to have at least 10 Iron Dome batteries, twice as many as the Israeli air force has now. They have teamed up with U.S. defense contractor Raytheon to develop a complementary system called David's Sling, which is designed to intercept longer-range missiles. Israeli officials acknowledge that the system does not guarantee an ironclad defense, and it remains unclear how it would fare in a sustained attack of long-range missiles.
U.S. officials say they are eager to continue funding Israel's missile defense systems, but lawmakers said in the spring that their continued support should compel Israel to share the technology and commit to continue developing it jointly.
In a gesture of appreciation for U.S. financial backing, Barak, the Israeli defense minister, gave Panetta a glass-encased model of an Iron Dome battery during a news conference at the Pentagon on Thursday.
"It doesn't explode," Barak said, drawing a laugh from his U.S. counterpart. "It cannot shoot — so don't worry."