Hezbollah and Israel have stepped back from the brink this time but the trajectory is deeply troubling

Mutual fear and aggression have reduced the immediate danger but both are diametrically opposed to one another and a future clash is certain

After a week of violence between Israel and the Lebanese militia Hezbollah, tensions have simmered down. The situation was quite different last Sunday, when hundreds of cars packed with terrified civilians fleeing southern Lebanon created traffic jams as they fled north after a volley of tit-for-tat strikes. After being hit by a series of drone and airstrikes, which killed two fighters and damaged its media centre, Hezbollah launched a retaliatory strike from southern Lebanon against Israeli army targets in the village of Avivim. Israel responded with artillery strikes on southern Lebanon. Yet despite the prospect of an all-out war between these two well-armed adversaries increasing in recent months, the balance of mutual fear and aggression inflicted by both sides has reduced the immediate likelihood of real conflict.

The latest escalation followed a wave of attacks attributed to Israel against Iran's non-state allies in Iraq, Syria and Lebanon. Israeli's increasingly aggressive posture against the network of Iran-aligned militias is trying to reverse, or at least stymie, some of the gains made by Tehran and its proxies in recent years. While the popularity of Iran and Hezbollah suffered from their involvement in the Syrian war on the side of the Assad regime, Iran's influence in the Levant has grown significantly since 2011. International negotiations with Iran during the Obama administration focused on curbing its nuclear programme, with its regional ambitions largely going unchecked. The Trump administration, for all its belligerent statements, has not done much to counter Iran's growing clout in the region.

Israel's more confrontational approach and the fiery war of words between officials and Hezbollah raised concerns about the prospect of renewed conflict. Following an Israeli attack on Hezbollah foreign fighters in Syria, the group's leader Hassan Nasrallah made an unusually frenzied speech a fortnight ago, threatening that from then on, Israel's drone flights over Lebanese airspace would no longer be tolerated and that the devices would be shot down by Hezbollah. Israeli Housing Minister Yoav Galant responded by threatening to "return Lebanon to the stone age", echoing previous rhetoric from other Israeli officials.

The bellicose exchanges have fuelled fear among Lebanese and Israelis of a repeat of the trauma of the last war in 2006, which was enormously devastating to Lebanon, particularly in the south. Most of the 1,000-plus people killed in Lebanon were civilians. Israel suffered significantly fewer losses. However, the low public tolerance for casualties and inability to definitively defeat Hezbollah on the battlefield left Israelis aggrieved and contributed to the downfall of then prime minister Ehud Olmert, who led Israel into the conflict.

Despite the recent fiery rhetoric, officials from both Hezbollah and Israel have been at pains to calm down tensions. In an August 31 speech, Mr Nasrallah walked back his vow a week earlier to shoot down Israeli drones, which continue to hover over Lebanon. Hezbollah's deputy secretary general, Naim Qassem, said the group would retaliate against an attack from Israel but not aim to start a wider conflagration. And Israeli Prime Minister Benjamin Netanyahu banned his ministers from passing judgment on the exchange of fire after Mr Galant's comment.

Other signs point to efforts on both sides to avoid war. Hezbollah’s retaliation against the Israeli strikes on its fighters in Syria, in the form of a cross-border attack against military targets and not civilians, is one such indication. Israel’s decision to significantly reduce the presence of soldiers along the border with Lebanon and replace them with mannequins in uniform was intended primarily as a deterrent and to avoid loss of civilian lives. However, by using this tactic, which appeared to ensure no soldiers were harmed in the Hezbollah attack, the Israeli Defence Forces also guaranteed there would be no pressure on government from the Israeli public to retaliate further. The Israeli counter-shelling following the Hezbollah attack largely pounded empty fields near Maroun Al Ras in southern Lebanon, to the bemusement of anchors on Hezbollah’s TV station.

Both sides are trying to avoid conflict because they know another war would be devastating. Hezbollah now holds an arsenal of more than 100,000 rockets and missiles that could hit any point inside Israel. This means that a strategy employed in previous conflicts to reduce the number of casualties in Israel, namely mass flight from the north to the south, would be less effective. In addition, Hezbollah now has dozens of precision-guided missiles that could hit strategic targets. Hezbollah fighters have also gained significant combat experience from the battlefields of Syria.

On the other side of the balance of power is the IDF, which has vowed that in the next war with Hezbollah, it would pursue the 2006 “Dahiya doctrine” of indiscriminate destruction of infrastructure and disproportionate force against communities thought to be supporting Hezbollah across the country. The IDF’s chief of staff said under the doctrine, nowhere would be considered safe and every village and neighbourhood would be treated as a military base.

A future war could also entangle war-weary Syrians, as Hezbollah and the Islamic Revolutionary Guard Corps have been increasing their presence and military recruitment across the country since 2012. Tehran is unlikely to be paying the salaries of tens of thousands of Syrian fighters to then let them simply sit out the next war.

More immediate concerns on both sides are limiting the prospect of war in the short-term. Hezbollah is still occupied in Syria, where its forces are stationed across the country, recruiting locals, establishing new bases and manning frontlines in the southern and western Aleppo countryside.

In Israel, this month's election, the second this year, also reduces the likelihood of war. Israeli officials have long vowed to destroy Hamas and Hezbollah militarily, and the Israeli public hopes and expects that they would follow through with that threat in the next conflict. The 2014 ceasefire in Gaza and 2006 end of hostilities in Lebanon were unpopular in Israel as the fighting ended before that goal was achieved. Israeli officials, however, know that destroying both Iranian proxies cannot be achieved without an immense cost and would most likely entail a bid to occupy Lebanon and Gaza and maintain a continuous military presence there, amid a hostile population that would undoubtedly rebel in an insurgency. It is therefore in Israel's interests to delay any combat with the two militias.

Warfare would be damaging to whoever is in power in Israel. It will result in large-scale destruction while failing to achieve that goal with limited civilian and military casualties. Mr Netanyahu has no reason to rattle the cage. He is currently projected to win the election and continue as prime minister, whether he forms a right-wing government or is forced into a unity government with his former ally Avigdor Liberman.

All these factors decrease the likelihood of war in the short and medium term but the overall trajectory is troubling. Israel and Iran are diametrically opposed to one another and perceive the actions of their adversary as aggressive, while regarding their own as defensive. Iran is determined to continue expanding its influence in the region. Israel, for its part, is resolute in stopping this expansion. We should expect future skirmishes between the two sides, increasing the likelihood of unwanted deterioration to an all-out war.

Russia, which could play a mediator role between the two sides, has other priorities. Within the Trump administration, some senior officials appear to goad Israel on instead of trying to reduce tensions. The balance of terror between the two sides can keep this conflict simmering without boiling over, but any serious miscalculation could lead to a horrifyingly violent conflagration. Those paying the price will be civilians in Lebanon, Israel and possibly Syria, who will be killed, displaced and lose their property. All efforts must be made to avoid this scenario.

Elizabeth Tsurkov is a fellow at the Foreign Policy Research Institute specialising in the Levant