As of Thursday afternoon, the Israel military said Iron Dome had intercepted 90 of an estimated 250 rockets fired by militant groups in the Palestinian territory in the previous 24 hours.
That ratio may not look particularly impressive, but the system is smart enough to ignore missiles that it detects are heading for open land or farmland. During previous but less intense barrages, the Israelis have claimed Iron Dome has brought down 85 per cent of the rockets it has targeted.
Successful hits by Iron Dome's interceptor missiles could be seen in palls of smoke high above southern Israel throughout the day.
"It's unbelievable, we are very pleased with how Iron Dome has been operating," said a spokesman for the Israeli Defence Force. "Even if the situation is very difficult for residents of southern Israel, we can only imagine what it would have been like without these defences."
Designed to operate at short distances, each interceptor costs Â£25,000, with the cost of each of the three or four batteries currently in operation estimated at Â£1.3 million each.
The system was built by the Israeli firm Rafael Advanced Defence Systems, though the extent of America's contribution has not been disclosed. Gen Martin Dempsey, chairman of the US joint chiefs of staff, acknowledged his country's involvement with the project during a visit to Israel last month.
He said the US military was "proud" to be "partners to a very successful initiative". Washington typically provides Israel with Â£2 billion worth of aid annually, most of it used for military purposes.
Some of those funds go towards the precision bombs deployed in strikes on Gaza since Wednesday that have killed 15 Palestinians, including at least seven Hamas militants, and caused collateral damage in congested areas.
The technology used by militant groups in Gaza is primitive by comparison. The majority of their missiles are home-made, unguided Qassam rockets, constructed with basic metal tubing and propelled by sugar and fertiliser.
Named after the Ezzadine al-Qassam Brigades, the military wing of Hamas, most hit open land and inflict no casualties.
"They are cheap, basic but nonetheless effective," said Col Richard Kemp of the Royal United Services Institute. "They are not the fireworks that people sometimes say they are. They are very effective if they hit their target."
Militants also have stockpiles of Russian-made Grad missiles and Iranian-made Fajr missiles. One of the latter is believed to have hit Rishon LeTzion, a town nine miles southeast of Tel Aviv, yesterday afternoon.
David Hartwell, senior Middle East analyst at IHS Jane's, said Gaza militants had come to rely on rockets as a means of spreading terror among Israeli communities after other options were severely limited by Israel's security measures.
"They rely more on luck than judgement, but they are effective as a weapon of terror because no one knows where they are going to land," he said.
Israel's multi-layered defence systems include David's Sling, also known as the Magic Wand, which intercepts medium-range rockets and missiles and is due to be operational in 2015.
The Arrow 2 and Arrow 3, jointly developed by Israel Aerospace Industries and the U Boeing, complete the multi-layered system, are designed for to intercept longer range missiles fired from Iran.