Why the relatively calm Lebanon-Israel border is heating up again

Armoured personnel carriers belonging to UN peacekeepers in south Lebanon are parked in front of a poster showing Lebanese Speaker Nabih Berri, Syrian President Bashar Al Assad and Hezbollah leader HaShow more

Over the past two weeks, tensions have flared up at the Lebanon-Israel border. And slowly but surely, the status quo that prevailed since the 2006 war between the Israeli army (IDF) and Hezbollah, the Iranian-backed Lebanese militia group, is eroding and the risk of a new conflict increasing.

On August 4 – exactly one year after the Beirut Port explosion – two rockets were fired at Israel from southern Lebanon. One landed in an open area while the other was intercepted by Israel's Iron Dome air defence system. No one claimed the attack, although Lebanese sources attributed it to unnamed Palestinian factions based in the area. The Israeli Air Force retaliated with air strikes, in response to which Hezbollah fired 19 rockets of its own the following day, aimed at the IDF near the occupied Shebaa Farms.

Fortunately, Hezbollah's rockets did not trigger further escalation; 10 of them were destroyed by Israel's air defence while the rest landed in unpopulated areas. However, these tit-for-tat strikes have been occurring with alarming frequency in recent months.

During its conflict with Hamas in Gaza three months ago, Israel was hit by three waves of rocket attacks from southern Lebanon. The number of projectiles – 13 – was limited and no casualty was reported. Likewise, on July 20, rockets were fired at Israel from the same location, a day after an Israeli air strike on Aleppo targeted a deployment belonging to Hezbollah and Iran's Islamic Revolutionary Guard Corps (IRGC).

These incidents are increasingly noticeable now because for 15 years, the Lebanon-Israel border has been relatively calm.

During the 1975-1990 Lebanese Civil War, the country's south had been a battleground for regional powers, while subsequent Israel-Hezbollah conflicts cost many lives. Since 2006, however, both sides have seemingly acknowledged the other's capacity to inflict devastating damages. Mutual deterrence enabled the status quo, which has remained intact despite the emergence of other regional crises such as the Syrian civil war. Israel and Hezbollah have routinely exchanged fire inside Syria over the past 10 years, especially in the area around the Golan Heights, but both sides seem to have had a tacit understanding to keep things calm inside Lebanon.

This has provided Lebanon with the longest period of calm with Israel since the end of its civil war. Recent developments, though, could shake things up.

Specifically, three questions about the exchange of fire this month need consideration.

First, Hezbollah did not take responsibility for the August 4 attacks. It did not do so for the May strikes either, although there are reasons to doubt any other group would have been responsible. Given Hezbollah's political grip over southern Lebanon, it is unlikely that a small Palestinian militia could fire rockets at Israel without its knowledge and approval. While such a scenario could imply that Hezbollah is not in complete control of its historical stronghold, this theory runs contrary to assessments made by western intelligence agencies and the UN Interim Force in Lebanon (Unifil).

The question, then, is why Hezbollah would allow another organisation to launch an attack on Israel and risk being drawn into a broader conflict. Perhaps, this is a way for the group to test the new Israeli government headed by Naftali Bennett and to see how committed Benjamin Netanyahu's successor is to preserve the status quo. Hezbollah's clashes with the IDF serve its domestic purposes, too. The group tends to point to its tensions with Israel for justifying the arsenal it has at its disposal, even though some politicians in Beirut have demanded the group's disarmament.

And yet, Hezbollah seems to have expended much of its political and social capital inside Lebanon.

It is, no doubt, capable of paralysing the political process in Beirut – as it has by way of preventing the formation of a genuinely technocratic government for the past several months. But its military intervention in Syria, the corruption cases involving its members and the economic sanctions imposed on Lebanon have weakened the movement it claims to lead. That there is popular resentment towards Hezbollah is evident from the recent clashes between its combatants and residents of the Druze village of Chouya, when the truck that the group was using to fire rockets at Israel was blocked by civilians enraged after being drawn into the crossfire. The truck was eventually returned, but such an episode would have been inconceivable a decade ago.

This leads to the third and most critical issue emerging from the recent developments in southern Lebanon: Iran's strategy for Hezbollah. The IRGC plays a central role in financing and training Hezbollah, which cannot take major military decisions without prior consultation with Tehran. Here, the timing of the attacks suggests co-ordination between Hezbollah and the IRGC. The rockets were launched only a few days after the attack on the Mercer Street, an Israeli ship crossing the international waters off the coast of Oman. Despite swift condemnation of Iran from both the US and UK, Tehran denied any responsibility for the attack. But the concomitance of these events is no coincidence, especially as it occurs in the middle of a political transition in Tehran, with Ebrahim Raisi having assumed the presidency on August 3. Under these circumstances, it may be Tehran – more than Hezbollah – that is testing the resolve of the Israeli government (and by extension of the US administration).

This leaves Lebanon in a dire situation. The increase in rocket exchanges with Israel in recent months indicates nervousness on both sides. Reflecting these tensions, Israel's Defence Minister Benny Gantz earlier this month said: "Lebanon’s situation is shaky. We can make it even shakier." Such a blunt statement was meant to deter Hezbollah from "testing" Israel's readiness. In this context, the risk of inadvertent escalation is high.

The ongoing talks at the UN in New York on the renewal of the Unifil mandate – due to expire by the end of August – are, therefore, crucial. Given recent developments, the presence of a robust UN force in the region will be critical in preventing future clashes.