Experts caution, however, that the skies are not nearly so clear as they seem. Israel has only three Iron Dome batteries, enough only to protect the cities closest to Gaza (Ashkelon, Ashdod and Be’er Sheva). At least three times as many would be needed to shield other population centers, and even with a special grant from Washington only three more are in the pipeline, for a total of six.

Nor is Israel’s umbrella against medium-range missiles yet on line. That system, known both as Magic Wand and David’s Sling, is due to deploy in about a year. It would aim to stop missiles fired from beyond about 50 miles, the outer range of Iron Dome. A third system, dubbed Arrow and already in operation, is designed to intercept ballistic missiles such as Iran’s Shahab-3.

“Magic Wand would be a great help, but it would not be enough,” says Yiftah Shapir, a retired Air Force intelligence officer at INSS. “No amount of defense is ever enough. Some rockets always get through.”…

Nor is it clear how well Iron Dome would perform in genuinely warlike conditions – that is, with missile barrages not in the dozens, but in the hundreds or even thousands. Elran warns that, however reassuring its performance over the weekend, the system still must be regarded as untested: “You can’t really make an extrapolation from what’s happened in the last 36 hours,” he says.