On Feb. 12, 2008, Imad Mughniyah, Hezbollah’s international operations chief, walked on a quiet nighttime street in Damascus after dinner at a nearby restaurant. Not far away, a team of CIA spotters in the Syrian capital was tracking his movements.

As Mughniyah approached a parked SUV, a bomb planted in a spare tire on the back of the vehicle exploded, sending a burst of shrapnel across a tight radius. He was killed instantly.

The device was triggered remotely from Tel Aviv by agents with Mossad, the Israeli foreign intelligence service, who were in communication with the operatives on the ground in Damascus. “The way it was set up, the U.S. could object and call it off, but it could not execute,” said a former U.S. intelligence official.

The United States helped build the bomb, the former official said, and tested it repeatedly at a CIA facility in North Carolina to ensure the potential blast area was contained and would not result in collateral damage…

The former official said getting the authority to kill Mughniyah was a “rigorous and tedious” process. “What we had to show was he was a continuing threat to Americans,” the official said, noting that Mughniyah had a long history of targeting Americans dating back to his role in planning the 1983 bombing of the U.S. Embassy in Beirut.