The intense rocket bombardment that Israeli civilians suffered last week was a reminder that the technologically sophisticated missile-defense system known as the Iron Dome does not provide absolute protection: several houses were destroyed, and one person was killed. Moshe Arens argues that Jerusalem’s strategic calculations must take this fact into account. (Free registration may be required.)

Some rockets get through [the defenses], while others send residents of the country’s south scurrying into bomb shelters. That spells the end of normal life for those who live there, and can be achieved by the launching of a few hundred simple, cheap rockets. The last few weeks have demonstrated this conclusively. Also, the Iron Dome system can be saturated by the launching of a number of rockets at the same target, some of which get through. The bombardment overwhelms the interception system. . . . The tremendous difference in the cost of the simple rocket and the expensive system operated to intercept it also makes it financially unsustainable in the long run.

It is true [that] the Iron Dome saves lives. It has been argued that it provides the government with the time needed to discuss a response to an initial attack. But it does not solve the basic problem: protection of the civilian population in southern Israel. . . .

The only way to stop the launching of rockets at Israel’s civilian population is by physically eliminating the enemy’s capability of doing so. That can be achieved only by troops on the ground—through the entry of the Israel Defense Forces into the launching areas and the destruction of the manufacturing and storage facilities. The belief that terrorist organizations dedicated to destroying the state of Israel can be inveigled to abstain from attacking Israel has proven to be false and is not likely to be borne out in the long run. . . . So long as these organizations continue to rule there, nothing will change.

Surveying news websites and social media on Sunday morning, I immediately found some intelligent and well-informed observers arguing that Iran deliberately warned the U.S. of its pending assault on Israel, and calibrated it so that there would be few casualties and minimal destructiveness, thus hoping to avoid major retaliation. In other words, this massive barrage was a face-saving gesture by the ayatollahs. Others disagreed. Brian Carter and Frederick W. Kagan put the issue to rest:

The Iranian April 13 missile-drone attack on Israel was very likely intended to cause significant damage below the threshold that would trigger a massive Israeli response. The attack was designed to succeed, not to fail. The strike package was modeled on those the Russians have used repeatedly against Ukraine to great effect. The attack caused more limited damage than intended likely because the Iranians underestimated the tremendous advantages Israel has in defending against such strikes compared with Ukraine.

But that isn’t to say that Tehran achieved nothing:

The lessons that Iran will draw from this attack will allow it to build more successful strike packages in the future. The attack probably helped Iran identify the relative strengths and weaknesses of the Israeli air-defense system. Iran will likely also share the lessons it learned in this attack with Russia.

Iran’s ability to penetrate Israeli air defenses with even a small number of large ballistic missiles presents serious security concerns for Israel. The only Iranian missiles that got through hit an Israeli military base, limiting the damage, but a future strike in which several ballistic missiles penetrate Israeli air defenses and hit Tel Aviv or Haifa could cause significant civilian casualties and damage to civilian infrastructure, including ports and energy. . . . Israel and its partners should not emerge from this successful defense with any sense of complacency.