Israel and the United States began a joint anti-missile defense drill Sunday morning, measuring responses to potentially paralyzing rocket fire on the homefront.

The training exercise, carried out every two years and dubbed “Juniper Cobra,” tests the serviceability of certain active missile defense systems, Israel Radio reported.

The five-day drill — first held in 2001 — measures military responses to missile attacks. Roughly 1,000 American soldiers arrived in Israel to participate in the drill.

The US has either jointly developed or financed all three tiers in Israel’s missile defense program — Iron Dome (short-range missile interceptor), David’s Sling (medium range) and Arrow (long range).

US Defense Secretary Chuck Hagel and Defense Minister Moshe Ya’alon reviewed preparations for the training exercise last week during Hagel’s two-day stay in Israel.

Hagel said it was the largest drill for US troops under the European Command.

“The exercise will employ Israel’s entire rocket and ballistic missile architecture, including Iron Dome, Arrow, and David’s Sling: assets that the United States is proud to have helped Israel finance and develop,” he said.

IDF Maj. Gen. Eyal Eizenberg, head of Home Front Command, said last week during a separate drill that the enemy of the future will employ tactics in order to try to paralyze Israel with missile fire, with the aim of sending its citizens into shock, reducing public morale, and forcing a quick ceasefire before the Israeli military can counterstrike.

At a press conference May 15, Hagel said that the Juniper Cobra exercise demonstrates the cooperation and commitment that the Israeli and American military jointly experience, and that “America’s commitment to a strong and secure Israel has not [been] and never will be anything but complete and unwavering.”