The formidable display of collective defense was the culmination of a decades-old but elusive U.S. goal to forge closer military ties between Israel and its longtime Arab adversaries in an effort to counter a growing common threat from Iran.

But the U.S.-led effort to protect Israel in the days and hours before the Iranian attack had to overcome numerous obstacles, including fears by Gulf countries at being seen as coming to Israel’s aid at a time when relations are badly strained by the war in Gaza.

Much of the cooperation Saturday night that led to the shooting down of the Iranian-directed barrage needed to be forged on the fly, and many details about the role played by Saudi Arabia and other key Arab governments are being closely held.