As hundreds of Iranian drones and missiles winged across the Middle East Saturday night, a defensive line of radars, jet fighters, warships and air-defense batteries from Israel, the U.S. and a half dozen other countries was already activated against the long-feared attack from Iran.

The operation was the culmination of years of U.S. effort to break down political and technical barriers that thwarted military cooperation between Israel and the Sunni Arab governments. Efforts to build an integrated air-defense system for the region date back decades. The initiative gained momentum after the 2020 Abraham Accords brokered by the Trump administration, which established formal ties between Israel and the United Arab Emirates and Bahrain.

“The Abraham Accords made the Middle East look different because we could do things not just under the surface but above it.” This nascent air-defense alliance had never been battle tested when on April 1, a missile strike in Damascus, Syria, killed several Iranian officers. Israel hasn’t claimed responsibility for the attack. Tehran quickly vowed to respond, and senior U.S. officials began pressing Arab government to share intelligence about Iran’s plans to strike Israel and to assist with intercepting drones and missiles launched from Iran and other countries toward Israel, according to Saudi and Egyptian officials.

The Iranian missiles and drones were tracked from the moment they launched. When the slow-moving Iranian drones came within range, they were shot down, mostly by fighters from Israel and the U.S. and in smaller numbers by British, French and Jordanian warplanes, officials said. An Israeli official involved in regional security cooperation efforts said that while there had been frequent sharing of intelligence on air-defense threats in the past, Iran’s attack Saturday “was the first time that we saw the alliance work at full power.”