Will the Israel-Hamas War Spiral into a Wider Conflict?

Iran’s direct involvement in the war is a nightmare scenario that would mark the transformation of the current conflict into a regional conflagration.

26 October 2023// United States Institute of Peace

Editor’s Note: This article was published shortly before reports that the United States launched air strikes on Iranian-linked targets in eastern Syria in response to attacks on U.S. bases in the region.

With the Israel-Hamas war poised to enter its fourth week, the conflict continues to escalate. The Israeli military announced on October 25 it had struck more than 7,000 targets inside Gaza, ranking the current military campaign among the most intense globally in recent memory. The conflict has resulted in an estimated 1,400 Israelis killed, according to Israeli government sources and more than 6,500 Gazans killed, according to the Hamas-controlled Health Ministry. More than 200 hostages are held captive in Gaza.

The siege and humanitarian crisis in Gaza are worsening daily. Hundreds of Israeli airstrikes are estimated to be hitting Gaza every day. The timing of an anticipated Israeli ground incursion remains uncertain but would mark a new, more dangerous phase of the war and put more than a million Palestinians at grave risk. Concerns are mounting — both in the region and beyond — that war could expand, reportedly prompting Biden administration officials to prepare contingency plans for the evacuation of more than 600,000 Americans living in Israel and Lebanon.

USIP’s Mona Yacoubian discusses the risks of this war expanding to Lebanon and Syria, the potential for an even broader escalation with Iran and what it means for the United States.

What are the risks of this war expanding to two fronts with Lebanon and/or Syria?

Lebanon is the most dangerous second front. Concerns are mounting that the current war between Israel and Hamas could expand with the opening of a second front on Israel’s northern border with Lebanon. Cross-border clashes between Israel and the Iran-backed, Lebanese militant group Hezbollah alongside Palestinian armed factions have occurred almost daily since the October 7. The fighting has led to casualties in both Israel and Lebanon, including at least 40 Hezbollah fighters, and forced the evacuation of many communities on both sides of the border.  

Yet despite mounting tensions, Hezbollah does not appear to have an interest in widening the war at this time. Lebanon is already on its knees, contending with unprecedented economic, social and political crises that have essentially rendered the country a failed state. Meanwhile, the Israeli government has long warned that its response to a Hezbollah-provoked war would be wide-ranging and devastating. As such, Hezbollah is keenly aware that it cannot afford to bring further ruin on Lebanon, or it would dramatically undermine its domestic support base.

Instead, its calculus seems to hinge on portraying unity with Palestinian factions while harassing Israel with limited strikes designed to fulfill its “resistance” narrative without plunging into all-out war. Yet this strategy is extremely risky in the highly volatile environs of the Israel-Lebanon border. The potential is high for miscalculation that erupts into a full-scale conflict. As a reminder, the 2006 Israel-Lebanon war began with a Hezbollah cross-border raid and kidnapping of two soldiers, but quickly spiraled into a brutal war lasting 34 days.

Beyond the possibility of unintended escalation, Hezbollah could also change its calculus depending on the trajectory of the Israel-Hamas war. If Hamas is on the verge of total destruction, or if an Israeli ground incursion leads to massive civilian casualties, Hezbollah — perhaps compelled by Iran — could opt to widen the war and open a second front with Israel. Much would depend on the circumstances and the reaction by the Arab and Muslim “streets.”