(Bloomberg) -- The bulldozers growling as soldiers sealed a tunnel that crossed beneath Lebanon’s border into Israel provided the kind of prop Benjamin Netanyahu loves. The Israeli prime minister told diplomats who’d braved fierce rains that Lebanon’s Hezbollah group was waiting for just such a foggy day to send attack squads burrowing into his country.

“Hezbollah wants to order several battalions into our territory with the aim of isolating communities, cities or kibbutzes, then go on a killing and kidnapping spree,” Netanyahu said afterward.

Weeks earlier, Lebanon’s foreign minister, Gebran Bassil, had brought diplomats to three sites in Beirut where Netanyahu had said Hezbollah was hiding missile upgrade facilities. Nothing to see here, Bassil told his guests -- no launchpads, no secret facilities to manufacture precision missiles.

“The most important response to Netanyahu is what the international media saw today,” Bassil said. “We build and they destroy.”

The dueling narratives highlight the potential for a new military conflict a dozen years after the last war between Israel and Hezbollah devastated the Shiite group’s heartlands in south Lebanon and the southern suburbs of the capital. The reconstruction of buildings, roads and bridges took years in Lebanon. Another war would be costly for all involved.

Potential for War

While Israel has contained its anti-tunnel operation within its borders so far, it may just be a preamble to a deadly showdown over Hezbollah’s missile program -- a key worry for Netanyahu as Iran and its Lebanese proxy dig in on Israel’s northern doorstep.

Israel sees its two foes as having become exponentially more threatening in the course of Syria’s civil war, where their forces have backed President Bashar al-Assad. The military intervention has allowed Iran to more easily transfer weapons to Hezbollah through Syria, and Iran has advisers, fighters and military hardware on the ground there.

While some analysts say Iran sought deterrence through its Syrian presence, Israel sees Iran’s position as offensive. On Monday, Netanyahu said the exposure of the tunnels was also designed to press for tougher international sanctions on Hezbollah and Iran.

Hezbollah has stayed largely silent on Israel’s tunnel claims, though Lebanese lawmakers have quoted the group’s ally, parliament speaker Nabih Berri, dismissing the allegations as an attempt by Netanyahu to distract attention from corruption allegations and his tottering governing coalition.

UN Confirmation

UNIFIL, the United Nations force charged with keeping armed fighters out of southern Lebanon, has confirmed the existence of one tunnel. The Israeli army said it has found three tunnels and expects to uncover more, without disclosing how many.

Lebanese Prime Minister-designate Saad Hariri, an ally of Iran’s regional rival Saudi Arabia, said early on that his government didn’t want Israel’s anti-tunnel operation to “constitute a reason for any escalation.” Yet Hezbollah dominates Lebanon’s politics, and its armed force is more powerful than the state’s.

Hezbollah both stretched and immeasurably strengthened since the last war. It’s still operating in Syria, where it has lost almost 1,700 fighters, according to the Syrian Observatory for Human Rights monitoring group. But its ranks have also swelled, and Israel estimates Hezbollah’s arsenal has expanded as much as 10-fold to 150,000 missiles.

Israel maintains it’s struck Hezbollah-bound arms convoys more than 200 times in recent years, severely limiting the group’s ability to upgrade missiles to precision quality. By taking diplomats to see the tunnel, though, Netanyahu sought to build international support in case Israel attacks missile facilities later, officials said on condition of anonymity to discuss policy.

‘Tip of Iceberg’

“The tunnels are the tip of the iceberg of a comprehensive offensive effort by Hezbollah. A much more hazardous part are the underground missile facilities,” said Michael Oren, Israel’s deputy minister for public diplomacy. “Hezbollah’s ability to hit any target in the State of Israel, whether it be our airport or oil refinery or any strategic target, poses an almost existential threat to our country.”

Hezbollah hasn’t responded to the allegations of Beirut weapons factories, though its leader, Hassan Nasrallah, has said it possesses precision missiles and can hit every part of Israel. Nasrallah’s threat to conquer Israeli border towns prompted Israel to begin its anti-tunnel search in 2015.

According to Israeli military officials and analysts, Hezbollah wants to seize Israeli towns at the start of any future war -- even temporarily -- to strike a psychological blow.

Israeli officials have sought to portray the tunnel discovery as a major setback for Hezbollah. Lebanese politicians and analysts questioned that claim.

“If Hezbollah were preparing for an offensive, then yes, destroying the tunnels would have an impact,” said Elias Hanna, a former Lebanese brigadier general. “But Hezbollah is not ready for that. It doesn’t have the right army or arsenal to do that.”

‘Already Useful’

Just by creating havoc on the Israeli side, the tunnels already have proven useful, said Ibrahim Bayram, a columnist for Lebanon’s an-Nahar newspaper.

“Hezbollah is content that it created concerns for its enemy,” Bayram said.

Though both sides say they don’t want war, the 2006 conflict -- which claimed some 1,200 lives in Lebanon and 165 in Israel -- began after a Hezbollah border raid escalated immediately.

Netanyahu “is taking prudent first steps to address this issue diplomatically,” said David Makovsky, director of the project on Middle East peace at the Washington Institute for Near East Policy. If he can’t create a diplomatic front against Hezbollah’s tunnels and missiles, “then it sets the predicate for going up the ladder.”

--With assistance from Ivan Levingston.

To contact the reporters on this story: Michael S. Arnold in Tel Aviv at marnold48@bloomberg.net;Dana Khraiche in Beirut at dkhraiche@bloomberg.net

To contact the editors responsible for this story: Riad Hamade at rhamade@bloomberg.net, Amy Teibel, Lin Noueihed

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