More than 450 people were killed and 1,500 wounded in Israeli airstrikes on southern and eastern Lebanon and the capital Beirut on Monday. The strikes mark a significant and threatening escalation of hostilities following an apparent Israeli attack that used explosive pagers (and other electronic devices) to kill members of the Lebanon-based Shiite militant and political group Hezbollah.

Israel and Hezbollah have been regularly firing rockets at Lebanon’s southern border for years. However, since Israel began its war in Gaza on October 7 in retaliation for Hamas attacks inside Israel, Hezbollah – a Hamas ally – has increased the frequency of its rocket attacks, hitting targets deeper inside Israel. Israel has also increased its attacks, and as a result, more than 110,000 Lebanese and about 60,000 Israelis have been displaced inside the country.

Last week, Israeli Defense Minister Yoav Gallant announced that Israel was entering a “new phase” in its ongoing war against Gaza and Hamas, in which the conflict with Hezbollah would take center stage. “The center of gravity is shifting north. We are shifting our forces, resources and energy north,” Gallant told members of the Israeli Air Force on Sept. 18, referring to Israel’s northern border with Lebanon.

Concerns that the conflict in Gaza could spark an all-out war between Israel, Hezbollah and their allies have been rife for nearly a year, but the latest waves of Israeli attacks represent a provocative escalation that could threaten the fragile balance of the more measured mutual rocket attacks that have become routine for Israel and Hezbollah.

Still, there are many unknowns: whether Hezbollah can or will respond with escalation; whether Israel is willing to launch a ground offensive in Lebanon, as it has done before with disastrous consequences; and whether the United States will – or can – constrain Israel and force it to withdraw.

Hezbollah has been in conflict with Israel for decades. The group is both a militia and a political party that holds seats in Lebanon’s parliament and provides services to the country’s impoverished Shiite community. Hezbollah was founded in the wake of Israel’s devastating invasion of Lebanon in 1982 and has fought Israel on several occasions, most recently in 2000 and 2006.

The latter war was particularly devastating, killing over 1,000 people and causing an estimated $2.8 billion in damage across Lebanon. The country has never fully recovered from that war; a government collapse, Covid-19 and the explosion at Beirut port in 2020 have plunged the country even deeper into crisis. The country cannot afford a full-scale war, and those in Lebanon who are not allied with Hezbollah would like to avoid a conflict like the one in 2006.

Whether that is possible remains to be seen. Israel has carried out a series of attacks on Hezbollah, including the alleged assassination of senior Hezbollah leader Fuad Shukr in July. The coordinated attack, which disabled Hezbollah’s communications system of pagers and walkie-talkies and was believed to have been carried out by Israel, wounded more than 3,000 people and killed at least 32, including children and the elderly, according to Lebanon’s Health Minister Dr. Firass Abiad. (Israel does not take responsibility for assassinations or attacks like last week’s; Hezbollah has blamed Israel for the attack.)

Israel began bombing targets in southern Lebanon on Friday, including suburbs and inland Beirut, killing a Hezbollah commander who had been with the organization since its inception during a meeting with other Hezbollah fighters. Monday, September 23, was reportedly the deadliest Israeli attack on Lebanon since the 2006 war.

There is a real possibility that these ongoing attacks could spiral out of control; Israel has already demonstrated its willingness to cross the Biden administration’s “red line” in the war against Gaza with its invasion of the city of Rafah in the Gaza Strip.

Hezbollah, meanwhile, must walk a fine line if it decides to retaliate – which is not a given, despite leader Hassan Nasrallah’s promise that Israel will face “just retribution and a bitter reckoning.” Hezbollah has reportedly fired 8,000 rockets into Israeli territory since October 7, some of them targeting the Israeli arms manufacturer Rafael and the Ramat David air base, both near the city of Haifa.

Hezbollah has stressed its solidarity with Hamas since the beginning of the Gaza war and has vowed to continue attacks on Israel until a ceasefire is reached. Both Hezbollah and Hamas benefit from Iranian financial and tactical support, but Hezbollah is much more aligned with Iran’s foreign policy goals than Hamas.

This has led to fears that Iran could be drawn into a regional war should the conflict between Israel and Hezbollah escalate. Even if Iran does not enter the conflict, a war between Hezbollah and Israel could be incredibly bloody: Hezbollah is larger and better armed than Hamas; should Israel indeed launch a ground offensive into southern Lebanon, there is a strong chance that it will face even fiercer resistance than in Gaza.

Still, there are reasons to believe Hezbollah might choose to de-escalate the conflict, including the fact that any war would almost certainly have devastating consequences for Lebanon, a country already struggling with a dysfunctional government and economic collapse.

“Hezbollah has several concerns,” Jon Alterman, director of the Middle East program at the Center for Strategic and International Studies, told Vox when it came to deciding its next steps. “One is maintaining Iranian support and aligning with Iran’s assessments and regional strategy. And the other reason is that 85 percent of Lebanese now live below the poverty line. The country is economically reeling, and if Hezbollah provokes a devastating Israeli attack on Lebanon, some Lebanese would see that as reckless and damaging.”

A diplomatic solution, such as Hezbollah agreeing to abandon its positions near Lebanon’s southern border, is certainly possible. That would allow Israelis to return to their homes in the north. Whatever the outcome, Israel is unlikely to eliminate Hezbollah, just as it failed to eliminate Hamas. And continued aggression could lead to even more extreme results in the future.