Standing at a border lookout on the Biranit base, his division headquarters, General Halevi pointed out Bint Jbeil, a city of perhaps 25,000 Shiites in southern Lebanon that endured some of the toughest battles in 2006, and, next to it, Maroun al-Ras, which he described as “a vacation village built by Iran” to hide a “post for monitoring what’s going on in Israel.” To the left was Ayta ash Sha’b, home to perhaps 7,000 Lebanese and “hundreds of rockets, missiles, I.E.D.s,” he said, referring to improvised explosive devices.

“We cannot shoot toward Ayta ash Sha’b because it is a village,” the general said. “This is a problem we somehow have to solve. The stronger the weapons, the stronger our response will be.”

He is responsible for a 75-mile border known as the “blue line” for the color of the barrels that mark the 2,700-square-mile area that has been patrolled by the United Nations Interim Force in Lebanon since 1978. Israel’s side is protected by a high-tech fence and countless cameras, but is still seen as porous: Part of the adjacent road is unpaved so troops can track footprints.

An M-16 rifle at his feet, General Halevi drove to the spot where two soldiers — Sgt. Eldad Regev and Sgt. Ehud Goldwasser — were abducted, and said simply, “July 12, 2006, 8:30 a.m.”

“Hezbollah was here on two sides, on the left in the bushes and just in front of us on that ridge,” he said. “When the patrol got to the road just beneath us, they opened fire.”

The first Israeli vehicle was attacked with machine guns, the second with a missile. Then, the general said, the enemy used explosives to blow through the fence and an iron gate. “Here started the Second Lebanon War,” he added.

Israel’s prosecution of that war was widely panned. General Halevi, who was commanding a brigade in the West Bank at the time, said preparations for the next round began immediately afterward, with the continuous development of a thick book — he declined to share it, of course — of operational plans, though he said the chance that they would be carried out exactly was “pretty low.”