More than nine months into its war with Hamas in the Gaza Strip, Israel now appears closer than ever to a second, even larger war with Hezbollah on its northern border. In June, the Israel Defense Forces announced that plans for a full-scale attack in southern Lebanon had been approved. And in mid-July, Hezbollah leader Hassan Nasrallah said that the Iranian-backed Shiite group was prepared to broaden its rocket attacks to a wider range of Israeli towns.

Although the possibility has received relatively little scrutiny in the international media, a full-scale war between Israel and Hezbollah would have consequences that dwarf the current Gaza conflict. A major Israeli air and ground assault against Hezbollah, the most heavily armed group in the Middle East, would likely cause turmoil across the entire region, and could prove particularly destabilizing as the United States enters a crucial stage of its presidential election season. It is also far from clear that such a war could be ended quickly, or that there is a clear path to a decisive victory.

The implications for Israel itself could be stark. Although Israeli air defense systems have been extremely successful thus far against missile attacks from Gaza, Lebanon, Iran, and Yemen, a total war with Hezbollah would be a whole different ballgame. According to Israeli intelligence estimates, Hezbollah’s weapons stockpile is more than seven times as large as Hamas’s and includes far more lethal weapons. Along with hundreds of attack drones, it includes some 130,000–150,000 rockets and missiles, including hundreds of ballistic missiles that could reach targets in Tel Aviv and even farther south—indeed, every point in the country.

Moreover, as previous wars attest, Lebanon is a treacherous battlefield. Israel’s last war with Hezbollah, in the summer of 2006, was inconclusive, and despite killing several hundred of the group’s fighters, it left the group’s military power largely intact. Hezbollah is also far better armed than it was then. Israel’s home-front command estimates that if a full-scale conflict broke out now, Hezbollah would launch some 3,000 rockets and missiles every day of the war, threatening to overwhelm Israel’s missile defenses. Israel would have to concentrate on defending crucial infrastructure and military bases, tell the civilian population to stay in bomb shelters, and hope for the best. It would be a challenge that far exceeds anything that Israeli leaders have faced before.

For now, both sides still have reason to exercise restraint. In fact, it seems that all the actors involved in the current conflict—Israel, Hezbollah, Iran, the Lebanese government, and the United States—have strong reasons to try to avoid a regional war. But even if the Biden administration manages to achieve an agreement between Israel and Hezbollah that includes a withdrawal of Hezbollah forces from the area around the border, Israel’s leaders may still find it hard not to respond to a domestic audience that favors dealing with Hezbollah once and for all. If Israel succumbs to that temptation without a clearly defined endgame or strategy for limiting the war, the results could be devastating.

THE BIG ONE

In contrast to its unexpected war in Gaza, Israel has long been preparing for a war with Hezbollah. Although Israel’s military leadership was caught completely by surprise by Hamas’s October 7 attack, it had for several years anticipated that Hamas might try to unite with Hezbollah and Iran’s other regional proxies in a coordinated multifront attack against Israel. In the years before his 2020 assassination by U.S. forces, Qasem Soleimani, who headed Iran’s Islamic Revolutionary Guard Corps’ Quds Force and supervised Iranian proxy forces across the Middle East, actively promoted a new strategy called “ring of fire”: by backing and arming a series of mostly Shiite militias, the Islamic Republic would gain influence in countries such as Iraq, Lebanon, Syria, and Yemen. At the same time, he tightened links with the Hamas-controlled Gaza Strip.

These militias, several of which sat on Israel’s borders, provided Iran with deterrence against Israel’s more powerful military and gave Tehran a ready launching pad for attacks. By early 2023, Salah al-Arouri, a senior Hamas leader who was then based in Lebanon and helped cement Hamas’s ties with Hezbollah, was talking publicly of the need to “unite all fronts” against Israel. To many Israeli officials, Hezbollah, as the most heavily armed and well trained of these Iranian proxies, posed the greatest threat. On October 7, as Hamas’s brutal assault was unfolding along the Gaza perimeter, Israeli leaders rushed to prepare for an even larger attack from Hezbollah in the north.

Thus, in the morning and afternoon hours of October 7, even as the IDF’s leadership frantically tried to save the southern Israeli communities and military bases around Gaza, it was also positioning massive numbers of troops on the Lebanese border in case Hezbollah decided to join in. Although this second task was little reported at the time, it proved much more successful than the first. In the south, where nearly 1,200 Israelis would be killed and 255 kidnapped by Hamas, the IDF took hours or even days to regain control. By contrast, in the north, three Israeli divisions, including tens of thousands of soldiers, were rapidly deployed and Hezbollah hesitated—missing the chance to strike an unprepared Israel. “Had they been quick enough,” one IDF division commander told me, “we would have managed to stop them only at Haifa”—Israel’s third-largest city, about 26 miles south of the Lebanese border.

In fact, the army’s northern command had been preparing for years for this challenge. Still, on October 7, Israeli forces at the border knew that everything depended on Nasrallah, Hezbollah’s secretary-general. Had Hezbollah acted more decisively, the situation probably wouldn’t have been much different than it was around Gaza. But Nasrallah chose to wait. Hezbollah did not respond until the following day, and then only by launching a limited number of rockets, drones, and antitank missiles toward IDF outposts and Israeli border communities. By that time, the IDF had made the huge deployment at the border and began returning fire, although neither side attempted to cross the border.

In fact, Hezbollah and its patron Iran had been taken by surprise on October 7, just as Israel had. As Israeli intelligence and Hamas sources later confirmed, Yahya Sinwar, Hamas’s leader in the Gaza Strip, did not notify his partners in Tehran and Beirut in advance of his intentions. In retrospect, the Israelis assess that had he confided in Iran and Hezbollah, they would have managed to intercept some of those messages and prepare to halt the attack. At the time, however, this was not known and Israeli officials feared the worst.

That day, the army made another fateful decision, approved by the Israeli government: all Israeli residents living within three miles of the northern border were ordered to evacuate. As a result, some 60,000 Israelis became refugees inside their own country, mostly staying at hotels around the country, including in Tel Aviv, financed by the state. At the time the order was issued, it was assumed that it would be temporary; no one guessed that these people would still be displaced more than nine months later. But as soon as these villages and towns in northern Israel had been emptied, Hezbollah turned them into a shooting range, rendering many of them virtually uninhabitable.

The common complaint among Israelis is that the evacuation of the north has given Hezbollah a three-mile security zone inside Israel, thus upending a status quo on the border that had more or less held since the 2006 war. The fact that twice the number of Lebanese citizens have been forced out of their homes as well, and from an area even farther away from the border, is of little comfort for the displaced Israelis. But arguably even more important in the immediate aftermath of October 7 was the outcome of an intense debate within the Israeli government about whether to launch a massive assault on Hezbollah itself.

DON’T DO IT

If some of Israel’s military leaders had their way, Israel might have launched a war against Hezbollah even before the IDF invasion of Gaza began. On October 10, U.S. President Joe Biden gave an important speech in which he promised American help to Israel against Hezbollah and Iran, including sending two aircraft carriers to the region. He also warned the Iranian leadership with one word: “Don’t.” Tehran took note. 

At the Kirya, the IDF’s Tel Aviv headquarters, some officers were weeping as they watched the president’s speech. This was the first good news since the horror of October 7 began. Nonetheless, a day later, Israeli Defense Minister Yoav Gallant and some of the generals tried to push Prime Minister Benjamin Netanyahu to approve a major operation against Hezbollah that apparently would include the assassination of senior Hezbollah leaders.

But Netanyahu knew that Biden’s “Don’t” was also meant for him. He also understood that a major attack on Hezbollah would very likely end up in a ground invasion of southern Lebanon, as well, and he doubted whether the army was up to the task of fighting vicious wars on multiple fronts, just days after Hamas’s massacre of Israelis on October 7. So Netanyahu did something quite strange, according to officials who were present that afternoon: he told his security detail to prevent Gallant from entering the prime minister’s office in Tel Aviv. By the time Gallant could get through, several hours later, the window of opportunity for an airstrike had been lost.

That evening, Netanyahu also decided to invite Benny Gantz and Gadi Eisenkot, two former chiefs of staff for the IDF who were leaders of the centrist National Unity Party, to the newly established war cabinet, a move that would allow the government to restrain some of the more hawkish ideas suggested by Gallant or the leaders of his other right-wing coalition partners. (With their military background, Gantz and Eisenkot were concerned that an immediate war in Lebanon would be too much for the IDF after the Gaza fiasco.)

As the war in Gaza has unfolded, the situation along the northern border has remained volatile. Although both sides have exercised a degree of restraint, Israel has decided to escalate on multiple occasions. In early January, Israeli forces assassinated Arouri, the Hamas leader, while he was staying in the Dahiya, the Shiite quarter in southern Beirut—crossing a significant threshold, since Israeli attacks as far north as Beirut have been rare in recent years. More recently, Israel has also assassinated three of Hezbollah’s senior commanders. Throughout the war, the Israeli air force has frequently struck weapons convoys and sometimes killed Hezbollah operatives in the Bekaa Valley, close to Lebanon’s border with Syria. As of mid-July, Hezbollah had confirmed the deaths of more than 370 of its fighters in Israeli strikes since the war in Gaza started. Dozens of Palestinian gunmen and Lebanese civilians have also been killed.

Hezbollah, in turn, has gradually increased the range and quantity of its own rocket attacks, and on the Israeli side, about 30 soldiers and civilians have died. Towns and villages on both sides of the border have been flattened. Israeli authorities say that more than 1,000 houses and buildings have been severely damaged as a result of Hezbollah attacks. There are similar assessments regarding damage on the Lebanese side. But the largest effect on Israel thus far may be the long-term displacement of tens of thousands of Israelis.

When the Israeli government told residents of towns near the northern border to evacuate, it was mainly responding to those communities’ initial fears that they could face a similar fate as their counterparts near Gaza: a surprise Hezbollah invasion of towns and villages that would result in horrific violence. During the past few months, however, there is far more concern about Hezbollah’s growing use of antitank rockets, which have a range of up to 6.5 miles and are highly accurate and difficult to intercept. They have caused much of the damage and many of the casualties in the north since the violence started.

THE RADWAN AND THE RIVER

At the center of the standoff between Israel and Hezbollah is the Shiite group’s occupation and arming of areas south of the Litani River, which flows through southern Lebanon not far from the Israeli border. According to the 2006 cease-fire agreement, Hezbollah was supposed to remain north of the Litani, with the land between the river and the Israeli border—the distance varies from about seven miles in the east to 20 miles in the west—under UN control; only the Lebanese army would be allowed to have a military presence there. But these measures were never implemented, and from the outset Hezbollah forces established de facto control of the border with Israel.

Thus, Israel’s most important demand is that Hezbollah units, and especially the group’s elite Radwan forces—special operations forces that are designed to conduct raids and cross-border attacks in Israel—must remain north of the Litani River. To the contrary, Hezbollah has said that it will accept a future cease-fire only if it provides for a return to the pre–October 7 status quo—in other words, allowing Hezbollah fighters to return south of the Litani. In such a scenario, the group would also likely seek to reconstitute the 20 military outposts it built along the border two years ago, which the Israelis bombed and destroyed shortly after the war in Gaza began.

Since late 2023, Amos Hochstein, President Biden’s special envoy to the region, has been trying to broker a cease-fire between Israel and Hezbollah. But Hezbollah has made clear that it will continue fighting as long as Israel’s war in Gaza continues. In early July, Washington launched a new push for a hostage deal between Israel and Hamas, which would include a cease-fire in Gaza while the first part of a prisoner swap is implemented. If that plan succeeds—the chances appear slim at the moment—the White House would immediately work to move the Israeli-Lebanese negotiations forward. As far as the northern front goes, the IDF’s leadership views a Gaza cease-fire as a “clutch moment” that would provide a chance to end hostilities in the north. 

But U.S. and Israeli assumptions about a détente with Hezbollah may be too optimistic. “It is hard to envision a long-term sustainable agreement,” Assaf Orion, former head of IDF strategy and a fellow at the Washington Institute for Near East Policy, told me. Given what he calls “Hezbollah’s overconfidence,” he says sees little prospect that a negotiated deal will be able to “answer Israel’s concerns about Hezbollah’s proximity to the border and the rocket threat.”

Even if Hezbollah agreed to Israel’s main demand and withdrew from the border, history suggests that it is highly unlikely that Hezbollah’s fighters will stay away permanently—or that any external player could enforce such a withdrawal. After Israel’s intelligence fiasco along the Gaza perimeter, how would Israel’s northern communities be reassured that the IDF will not miss similar signals on the Lebanese border? It is already clear that the IDF will have to permanently deploy significant forces in the north and around Gaza. Even then, however, it will be up to residents of these areas to decide whether the situation is safe. If they are not convinced, many of them won’t return.

Shimon Shapira, an Israeli analyst of Hezbollah, believes that Nasrallah hopes to avoid a full-scale war with Israel. Yet he sees further escalation—even if unintended—as entirely possible. One side might decide to strike a preemptive blow against the other, fearing that its opponent was planning a similar surprise attack. For example, if Hezbollah maintains its forces in the south on high alert, Israeli military intelligence could mistakenly assume that the group is preparing for an immediate operation and respond with massive force.

The calendar may also contribute to heightened support in Israel to take on Hezbollah soon. With the school year beginning on September 1, many families from the north are losing patience. Heads of local municipalities in the north fear that without government action many families will choose to leave the region for good. The Netanyahu government has gained notoriety for neglecting communities on the frontlines of the war—and although a special office was established to deal with the needs of southern residents, no similar action has been taken in the north. In recent weeks, opposition leaders have seized on the government’s failure to address security around the northern border, and Netanyahu may conclude that time is running out.

DAMNED IF YOU DO

The unsustainable situation on the northern border has left the Israeli government in a dilemma. Although Netanyahu and Gallant have threatened Hezbollah and the state of Lebanon with absolute destruction if Hezbollah launches an all-out war, neither seems keen on such a scenario now. 

It is worth recalling that Hezbollah was itself established in the wake of Israel’s first invasion of Lebanon in 1982, in what is now known as the First Lebanon War. By 2000, Hezbollah had been able to drive the Israelis out of their self-proclaimed security zone in southern Lebanon, forcing the IDF’s full withdrawal over growing Israeli public concern about military casualties. Then, the war that broke in July 2006 ended after 34 days in a miserable draw that left both sides unhappy but also wary of another massive direct confrontation. Many Israeli analysts suspect that Hezbollah has prepared itself rather well for the next round.

If Israel is drawn into a full-scale war, it is reasonable to assume that the IDF will mostly prefer a standoff conflict, in which it relies primarily on its air superiority and accurate strike capabilities. Israeli generals would probably also stage a ground incursion, but it is doubtful that they would have Israeli forces continue north of the Litani. Such a move would risk spreading their forces too thin, especially if the war in Gaza continues during that time. And any decision to attack will have to take into consideration Israel’s rather limited available manpower after nine months of fighting in Gaza. In July, the Knesset approved a bill to extend mandatory military service to three full years in an effort to make up for troop shortfalls.

Israeli officials have also hinted that the army is facing a severe shortage of accurate bombs and shells in Gaza, which could place significant constraints on a simultaneous offensive in Lebanon. As for ground forces, in spite of the relative military success achieved in Gaza, the challenge in Lebanon would be different. Although South Lebanon would presumably be almost empty of civilians, Hezbollah is far more sophisticated than Hamas. The IDF would probably be capable of winning the battle of South Lebanon, but it might come at a high cost to its forces. Israel would also have to consider the risks for its entire home front, including cities such as Tel Aviv and Haifa, which would likely be exposed to continual rocket attacks, including more sophisticated guided missiles that Hezbollah has received from Iran in recent years.

Some Israeli politicians and generals maintain that there is a middle way: by ramping up military pressure on Hezbollah for a few days, the thinking goes, Hezbollah, fearing an all-out war and the destruction it would unleash on Lebanon, would balk and withdraw from the border. This is a dangerous case of wishful thinking. In reality, once this kind of escalation was underway it would be very difficult for Israel to dictate to Hezbollah when the war should stop. If, for instance, Netanyahu decides to strike targets in Beirut, Nasrallah might decide to respond in kind by hitting Tel Aviv. And if a part of such an attack got through Israel’s antimissile defenses, there would be enormous pressure for a larger war that would inevitably threaten the civilian populations of both sides.

For the moment, both sides continue to seek to restore deterrence, in spite of escalating attacks. Nasrallah has talked publicly of a strategic equation, in which his group chooses targets in response to Israeli actions. Both sides are fully aware of the devastation that would be wrought in a full-scale war. Israeli airstrikes could bring massive destruction to all state-owned civilian infrastructure in Lebanon within a few days. It’s unlikely that Gulf states would volunteer to foot the bill after such devastation—and until now, Iran had been willing to directly assist only Hezbollah and the Shiite community in Lebanon. Hezbollah, in turn, with its huge arsenal, could send Israelis into bomb shelters for weeks on end.

If a full armed conflict does occur, it may not be brief. There’s a chance that Hezbollah, with Iran’s encouragement, would attempt a war of attrition, hoping that this would gradually lead to Israel’s collapse, the way Tehran’s hard-line leaders have imagined it. Following the war in Ukraine from afar, many Israelis have been fearing that they would face a similar scenario: a never-ending war, designed to exhaust the country’s willpower and capabilities, until it succumbs to outside pressure. What they didn’t anticipate, given Hamas’s brutal invasion and attack on Israeli communities on October 7, was that Israel would indeed find itself in Ukraine’s shoes but, as it sought to defend itself, would be treated instead, by many Western countries and in the international media, as another Russia, almost a pariah state. (The Russian government, of course, is glad to see the prolongation of the war in Gaza, because it diverts Western attention and U.S. resources from its own bloody campaign in Ukraine.)

NO WAY OUT

During the Israel-Hamas war, I have made a point of visiting the norther border of Israel every two or three weeks, in order to follow events on this second front of the war, which could yet become the primary one. It has been a frustrating experience. Once Israel’s most beautiful region, it is now scarred with medium-intensity military conflict. Many houses in villages along the border are totally destroyed, mostly by Russian-made Kornet antitank rockets—supplied to Hezbollah via Iran—which cause more damage than the Katyusha rockets that Hezbollah relied on in the past.

In one of my recent visits, I went to the Shebaa Farms, the contested area on the eastern part of the northern border which Israelis call Mount Dov. An IDF brigade commander told me that when soldiers from certain outposts now go on leave, they have to leave on foot, because it is too dangerous to allow large vehicles to enter an area that is continually exposed to Hezbollah’s antitank rockets. Along the road to one outpost, I could see the remains of a civilian truck hit by a rocket in April. Its driver, an Arab Israeli citizen, had been killed.

In mid-July, I went to see a friend, an army reserve officer who has been on active duty since October. He lives in a kibbutz in the western Galilee, about a mile from the border, and serves nearby. His family is now considering returning to their house after nine months of forced exile. The kids miss home. (Although it is up to families themselves to decide whether to return, few have done so.) And yet he still does not see a way out any time soon. “We have been defending rather well, but these tactical achievements do not converge into a strategic victory,” he told me. “Most of what we do is only a reaction to alterations along the border.”

If the situation explodes, however, the border region—and both countries—will experience something they have never encountered before: a full-blown war that will include unprecedented damage to civilian populations and national infrastructure. The current war in Gaza has already shown how easy it is for this kind of conflict to get prolonged. And judging from past wars between Israel and Lebanon, it is unlikely that it would come to a satisfying end.