MENAHEM KAHANA / AFP / GETTY IMAGES An Israeli missile is launched from the Iron Dome missile system in the southern Israeli city of Beer Sheva in response to a rocket launch from the nearby Palestinian Gaza Strip, Nov. 15, 2012.

Military gear-heads like to boast about how this or that latest technology that they’re fond of – or that their company, or country, is pushing – is a “game-changer.”

The major-combat debut of Israel‘s Iron Dome missile-defense shield over the past several days may be one of the few that can legitimately make that claim.

It is destroying about 90% of the rockets and missiles that Hamas, the Palestinian political party governing Gaza, is firing into southern Israel, Israeli officials say.

One battery of Iron Dome anti-missile missiles downed 100% during a salvo, a senior Israeli official tells Battleland.

“We’ve got about a 90% success rate,” he says, proudly giddy. “This is unprecedented in history.” It’s also impossible to confirm, but the lack of Israeli casualties suggests Iron Dome is the most-effective, most-tested missile shield the world has ever seen.

(PHOTOS: A New Gaza War: Israel and Palestinian Militants Trade Fire)

“We keep tweaking it,” says the senior official, who declined to be identified. “In one of the recent exchanges, one of the batteries was 100% [successful]. That means, to me, that Iron Dome is capable of 100% [across the board] — I don’t think it was entirely a fluke.” He said he didn’t know how many missiles and interceptors were involved in the salvo; an Iron Dome battery typically consists of a radar unit and three launchers, each outfitted with 20 Tamir interceptor missiles.

The bottom line: the more rockets Hamas fires, it seems, the better at stopping them Iron Dome becomes.

They’re playing a game of aerial attrition: who will run out of missiles first?

The missile shield’s success came as Israel broadened its attacks on Hamas-related sites in Gaza over the weekend, launching air strikes against political sites – including the headquarters of the Hamas prime minister – as well as military targets.

“There’s no country on Earth that would tolerate missiles raining down on its citizens from outside its borders,” President Obama said Sunday in Thailand, his first destination on a three-stop, three-day tour of southeast Asia. “So we are fully supportive of Israel’s right to defend itself from missiles landing on people’s homes and workplaces and potentially killing civilians.”

Iron Dome impressed Defense Secretary Leon Panetta in August during a tour of a battery while he was in Israel. “Iron Dome has had a better than 80% success rate at hitting rockets fired from Gaza into Israeli population centers, and it has successfully intercepted more than 100 rockets,” he said shortly after he returned. “We can be proud of this system’s record of saving lives and preventing wider conflict in that region.”

(MORE: The Israeli Assault on Gaza: How Surgical is Surgical?)

As of Sunday, Hamas had fired close to 1,000 missiles and rockets into Israel. Iron Dome decided — by tracing their trajectory and likely impact points within seconds of launch — that about two-thirds didn’t pose a threat and let them fall harmlessly to Earth. It destroyed about 90% of the remaining 300 or so that threatened to land in populated areas, Israeli officials said.

Consider for a moment what a game-changer such a capability represents:

— Shielded under Iron Dome, the Israeli government can take the time it feels its need to plan its response because it is not under the pressure that hundreds of explosions potentially killing hundreds of Israelis would generate. “The best, from our perspective, is that it gives us time,” the senior official says. “If we were being hit by this amount of rockets without Iron Dome, we would have to resort to other means” – including a ground invasion, which he still fears may happen. That could kill “thousands” of civilians, he says, as the Israeli military cleared Gaza of missiles and missile factories. — It saves lives. — It saves infrastructure, including dwellings, buildings, utilities and roads. — There is perversely, a downside to its success: it frustrates the enemy. “It denies what Hamas can claim as a victory, so it can prolong it,” he says of the aerial assault. “One can conceive of a situation where Hamas can say, `Look, we struck Tel Aviv, we struck Jerusalem – let’s have a victory parade and call it a war.’ They haven’t been able to do that.”

The senior Israeli official says the system’s battle management software is sensitive enough to monitor the trajectory of incoming missiles. “It distinguishes whether it is going to hit downtown or an open field,” he says. “If it’s going to hit an open field we don’t shoot at it.”

That’s important because the interceptors cost up to $100,000 each. That’s pocket change – heck, pocket lint – to the U.S. military, but relatively costly to the Israeli government, especially compared to the incoming rockets, which “are basically free” to Hamas, the official says (they can cost less than $1,000).

(MORE: Psychological Warfare with Missiles: Why Tel Aviv Matters)

Iron Dome “is actually a money-saver,” he adds. “Think if these rockets actually hit a neighborhood, in terms of the human costs, the wounded, the destruction of infrastructure would be much greater. So $100,000 is not that much to pay for a house that’s full of kids.”

Iron Dome was developed by Israel’s Rafael Advanced Defense Systems Ltd., and is expected to cost close to $1 billion by the time up to 15 batteries are bought (five are now deployed in southern Israel). The U.S. has pledged about $300 million to help fund the effort. Israel decided to build the system after the 2006 Second Lebanon War, when 4,000 Hezbollah rockets rained down on northern Israel, killing 44.

Iron Dome is designed to counter short-range missiles with a range of 70 kilometers or less – about 45 miles. Its prey includes crude Katyusha and Qassam rockets and Soviet-designed but built-in-Gaza Grads, with a range of up to 25 miles. The mobile system saw its first real-world test in April 2011, when it downed a Gaza-fired Grad in April 2011. Hamas said it had launched an Iranian-made Fajr-5 missile, with a range of up to 45 miles, toward Tel Aviv this past weekend, but Israel said they shot it down, too.

As of Monday, 91 Palestinians had died in the Israeli counter-attacks, with 700 wounded, according to Palestinian officials.

“We have had casualties,” the senior Israeli official concedes, including three killed and 68 wounded. “But the casualties we have had – the three killed – was not because of Iron Dome, but because the people didn’t listen to the siren – they thought they were out of range.”

The hype continues. But in this case, for a change, it might be warranted.

MORE: Has Israel’s Assault on Gaza Made Tel Aviv Vulnerable?