Redesigning the Security Space on the Israel–Lebanon Border

Executive Summary

There is a strategic framework for transforming the volatile security situation along the Israel–Lebanon border. There is a historical evolution of the boundary from its 1921 demarcation to the current “Blue Line,” and political weakness in Lebanon, UN ineffectiveness, and Iranian influence allowed Hizbullah to entrench itself as a dominant military force in southern Lebanon. Israel’s recent military successes create an opportunity for a new, sustainable border arrangement emphasizing demilitarization, sovereignty restoration, and robust international oversight. This vision demands sustained U.S. leadership, international cooperation, and domestic political resolve, recognizing that true border security can only arise from a redefined strategic order on the ground.

A Shifting Border Line

In early 1921, two lieutenant colonels, Britain’s Newcombe and France’s Paulet, set out to mark the border between Palestine and Lebanon, from the Mediterranean to Al-Hamma at the Yarmouk. Over three weeks, they drove the route and marked the border with 71 stone cairns; later these were replaced with concrete pillars and piles of concreted stones. The Newcombe–Paulet Commission’s report was accompanied by a written document and a map script.

From 1923 to 1948 the border line underwent many changes and refinements. During World War II the British re-marked the border when their army conquered Syria (then controlled by Vichy France) and handed it over to General de Gaulle’s Free French. The re-marking was done while British forces were in the country, using state-of-the-art surveying equipment for the time, and numerous errors from the 1921 demarcation were found. Border points were marked with concrete posts known as boundary pillars.

After Israel’s War of Independence, the Israel–Lebanon Armistice Agreement of 23 March 1949 set the international boundary as the armistice line between Israel and Lebanon. As part of the armistice arrangements with Egypt, Jordan, Lebanon, and Syria, Mixed Armistice Commissions (MACs) were established, including with Lebanon.

The Israel–Lebanon MAC also worked on marking the armistice line by placing piles of concreted stones painted white, with two metal flags and the inscriptions “Israel” and “Lebanon” pointing in opposite directions. The MAC did not resolve all disputes before the Six-Day War began, at which point border talks effectively ceased.

Today, the line separating Israel from Lebanon is the line fixed when the IDF withdrew from the areas it entered in 1982. Upon Israel’s withdrawal from Lebanon on 24 May 2000, it was agreed with the UN to delineate a redeployment line, slightly different from the international boundary, called the “line of withdrawal of IDF forces from Lebanon,” also known as the Blue Line (based on the UN flag’s color).

The UN marks the line on the ground with large barrels and concrete blocks painted blue. It is a provisional line that mostly, but not entirely, overlaps the Israel–Lebanon armistice line, with an understanding between Israel and the UN that the final line will be set in a joint Israel–Lebanon negotiation. Fourteen points of dispute remain.

The Border as a Volatile Strategic Front

Israel’s northern border with Lebanon, especially since the events of 7 October 2023 and the ensuing northern campaign, has emerged as a volatile strategic front that requires fresh thinking. This proposal examines the inherent, persistent failures of past border arrangements, analyzing why they repeatedly failed to enforce Lebanese sovereignty and to prevent Hizbullah’s consolidation as a strategic military actor. It argues that Israel’s military successes in its various confrontations with Hizbullah, particularly in the current war, have created a unique lever that enables the Lebanese government, with international backing, to reassert sovereignty in the south. That, in turn, has far-reaching implications for Israel’s claims to change the status quo. The paper proposes a new paradigm for stabilizing the border, based on a phased (“pulse”) approach: creating an expanded security zone, completely demilitarizing southern Lebanon of Hizbullah forces, and deploying an effective multinational force led by the United States, while preserving Israeli aerial freedom of action in the initial stages until full stabilization. Finally, it discusses the international and domestic challenges of implementing this option and the need for broad understandings and sustainable enforcement mechanisms.

Introduction: The October 7 Earthquake and the Need for a New Northern Security Paradigm

The events of 7 October 2023 and the war that followed not only exposed the severe vulnerability of Israel’s southern borders; they also dramatically highlighted the escalating threats on the northern border with Lebanon. The intense fighting with Hizbullah—mass rocket fire, UAV launches, and ground maneuvers—forced large-scale evacuations of Israeli communities and proved that the existing security concept, grounded in UN Security Council Resolution 1701, collapsed completely. The Blue Line, intended to mark Israel’s withdrawal from Lebanon and ensure the south’s demilitarization, has de facto become an active frontline.

This reality compels a thorough re-examination of the strategic assumptions that have shaped Israel’s Lebanon policy in recent decades. This paper analyzes the roots of the continuing failure to regulate the border, reviews the legal-international dimension of the dispute, and presents a comprehensive strategic alternative for redesigning the security space on the northern border. The alternative builds on lessons of the past, recognizes the complex geopolitical reality, and offers a phased, sustainable framework anchored in significant international commitment under leadership other than the UN, which has failed in its role.

Part A: Historical and Geopolitical Background—A Chronicle of Instability and Failed Sovereignty

Lebanon: An Artificial and Fragile State Turned “Hizbullah-Land”

By virtue of its multi-sectarian demography and fragile political system, Lebanon has suffered chronic instability since its founding. The Taif Agreement (1989), which ended the long civil war (1975–1990), was meant to lay a foundation for a functioning state but in practice left sectarian power centers and external interests that continued to undermine stability. Israel’s withdrawal from the Security Zone in May 2000, though carried out in accordance with UN decisions, created a governance vacuum in southern Lebanon. Hizbullah, with Iranian and Syrian support, quickly and efficiently exploited this vacuum, transforming itself from a local guerrilla force into a semi-state military actor with strategic capabilities threatening Israel.

The establishment of a “Hizbullah state,” especially in the south, complete with an independent military apparatus, social and economic networks, and a parallel political system, directly challenged Lebanese state sovereignty. Weak and divided Lebanese governments avoided direct confrontation with the organization, thereby enabling it to systematically violate UNSCR 1701. That resolution, adopted at the end of the 2006 Second Lebanon War, called for disarming all armed groups in Lebanon, deploying the Lebanese Armed Forces (LAF) as the sole sovereign force south of the Litani, and preventing the entry of weapons to the area without government approval. In practice, Hizbullah was not disarmed; it dramatically upgraded its capabilities, building a stockpile of tens of thousands of rockets and missiles, including precision missiles, and creating a constant strategic threat to Israel’s home front.

The Current Line (Blue Line): Anatomy of a Strategic Failure

The Blue Line, drawn by the UN in 2000, was never intended as a permanent international boundary but as a line of withdrawal. It stretches roughly 79 kilometers, from the Mount Dov/Hermon area in the east to Rosh Hanikra on the Mediterranean coast in the west. Complex mountainous topography, Lebanese-side commanding ridges, dense forests, deep wadis, severely hampers the IDF’s observation and control and gives Hizbullah an inherent tactical advantage. Many Lebanese villages—Maroun al-Ras, Bint Jbeil, Aita al-Shaab, and others—sit dangerously close to the border, often overlooking Israeli communities. Hizbullah exploited this proximity to embed military infrastructure within civilian populations, cynically using civilians as human shields, and to mount attacks and indirect-fire salvos into Israel.

The strategic vulnerability of Israel’s frontline communities—Metula, Kiryat Shmona, Shlomi, Manara, and many more—has been tragically demonstrated since October 2023. ATGM fire, short-range rockets, mortars, and UAVs became daily routine, causing heavy property damage, harming vital infrastructure, and paralyzing civilian life. The necessity to evacuate tens of thousands of residents for many months inflicts a severe blow to national resilience and Israeli sovereignty.

Part B: Diagnosing Past Border-Regulation Failures—Why the Existing Model Keeps Collapsing

Past attempts to stabilize the Israel–Lebanon border, especially arrangements rooted in international decisions, have failed systematically. This is not accidental but stems from a toxic mix of structural, political, and strategic factors:

• Inherent weakness of the Lebanese state and inability/unwillingness to enforce sovereignty: Lebanese governments have been weak, divided, and influenced by sectarian and external actors. They lack the military and political capacity to confront Hizbullah and enforce sovereignty across the country, particularly in the south. The LAF, despite some international support, remains secondary to Hizbullah’s military power and at times must coordinate with it. Any attempt to challenge Hizbullah risks renewed civil war—a threat all Lebanese political actors fear.
• Failure of UNIFIL and the UN as a monitoring/enforcement mechanism: UNIFIL, charged with supervising implementation of 1701, has proven toothless and ineffective. Its limited mandate, dependence on cooperation from the LAF and Hizbullah, and lack of real enforcement capability render it largely symbolic. UN reports have at times noted Hizbullah violations but did not produce meaningful corrective action. As an institution, the UN has repeatedly shown itself incapable of dealing with state-sponsored terrorist organizations operating from within civilian populations, failing to create effective enforcement mechanisms or impose meaningful sanctions on Lebanon for non-compliance.
• Iranian intervention turning Lebanon into a forward front in a regional struggle: Iran views Hizbullah as a central strategic arm of the “Resistance Axis” and regional-hegemony bid. It funds, arms, and directs the organization, turning Lebanon into a forward base against Israel. So long as Tehran’s interest in holding Lebanon hostage endures, any local arrangement will remain vulnerable to Iranian pressure and sabotage. The transformation of southern Lebanon into an Iranian outpost is the chief driver of chronic instability.
• Cynical exploitation of international law and the civilian sphere by Hizbullah: Hizbullah operates from within and behind civilians, exploiting protections in international humanitarian law. It places military infrastructure—arms depots, HQs, launch sites—inside residential areas, schools, and hospitals, complicating the IDF’s response and confronting Israel with moral-legal dilemmas. In parallel, Hizbullah runs an effective international propaganda apparatus portraying itself as a “legitimate resistance” and accusing Israel of “war crimes.”
• Lack of genuine international commitment to change the situation: Despite broad recognition of the Hizbullah danger, the international community, particularly Western powers, has not shown sufficient resolve to compel Lebanon to assert sovereignty or disarm Hizbullah. Economic interests, fear of regional escalation, and differing conceptions of the conflict have prevented the creation of a united, forceful front.

Part C: Implications of an Israeli Victory over Hizbullah for Lebanon’s Status and Israel’s Claims

Israel entered the current northern campaign with a clear position: the pre-October 7 reality cannot continue. This proposal assumes the campaign ended with significant Israeli military gains—Hizbullah forces pushed away from the border, substantial degradation of its military capabilities, a marked reduction in its dominance within Lebanon, and restored security for northern residents. Such an Israeli victory, even short of Hizbullah’s total dismantlement, creates a new strategic reality with far-reaching legal and political implications:

• Lebanon’s duty to restore sovereignty: With the immediate military threat of Hizbullah in the south neutralized, Lebanon’s chief excuse for failing to enforce sovereignty disappears. With Hizbullah significantly weakened, the Lebanese government, backed internationally, can and must deploy its army effectively along the border, enforce the law, and prevent any renewed entrenchment by armed non-state actors.
• Strengthening Israel’s claims for territorial and security changes: Lebanon’s persistent failure to meet its international obligations (notably 1701), coupled with Israel’s repeated need to act militarily to remove threats emanating from Lebanese territory, bolsters Israel’s argument for substantive changes in security arrangements. The principle of “territory in exchange for real security” becomes salient.
• Implications under international law: A situation in which a state consistently allows a terrorist organization to operate from its territory and attack a neighbor raises sharp questions of state responsibility. An Israeli victory that enables Lebanon to reassert sovereignty strengthens the case for holding Lebanon legally and politically accountable to prevent renewed aggression from its soil.

Part D: Paradigms and Options for a New Border Design—A Phased Proposal

History shows that durable border arrangements require more than paper agreements. They demand physical changes on the ground, robust monitoring and enforcement mechanisms, and broad international recognition. The Korean DMZ, the Lausanne Treaty (1923), and Camp David (1979) between Israel and Egypt offer key lessons:

• Korean DMZ: A 4-km-wide buffer, tightly supervised by international (mainly U.S. and South Korean) and North Korean forces, has prevented all-out war on the peninsula for over 70 years despite no formal peace treaty.
• Lausanne Treaty: Redefined modern Turkey’s borders after World War I and the Ottoman collapse, creating a relatively stable territorial reality.
• Camp David: Returning Sinai to Egypt was made possible by complete demilitarization of the peninsula’s offensive weaponry and deployment of an independent, more effective Multinational Force & Observers (MFO) rather than a UN force.

Drawing on these lessons, and recognizing the collapse of the current model, this study proposes a phased (“pulse”) strategic alternative to redesign the Israel–Lebanon border security space:

Phase A: Create a New Security Reality and Ensure Initial Israeli Freedom of Action

• Translate military gains into security gains: Rigidly enforce Israel’s military outcome so that all Hizbullah forces and infrastructure are pushed a significant distance from the border, at least to the Awali River, and beyond in select areas. Destroy all of the organization’s underground infrastructure and strategic weapons stockpiles across Lebanon.
• Maintain full Israeli aerial and intelligence freedom of action: In the initial period, until a reliable alternative security mechanism stabilizes, Israel retains full aerial and intelligence freedom of action over all Lebanese airspace to prevent Hizbullah’s re-entrenchment, thwart arms smuggling, and respond immediately to emerging threats. This freedom will gradually decline as the multinational force and LAF demonstrate capability and effectiveness.

Phase B: Establish a Demilitarized, Supervised Security Zone Led by a U.S. Force

After Hizbullah is verifiably disarmed, define an expanded security zone: Establish a substantially wider security zone to the north of the Blue Line, extending from the international boundary north at least to the Litani River and beyond in topographically critical areas. This zone will be fully demilitarized of any military or armed presence other than the IDF in the first stage and later LAF and a dedicated multinational force.

• Blended recommendation—new defensive border concept: Base the Israel–Lebanon boundary on a demilitarized buffer inside Lebanon under a U.S.-led force combined with a multi-layered defensive belt inside Israel.

Core principles:

• • Effective control: Combine international actors with Israel’s smart technological control.
  • Prevent terrorist re-entrenchment: A meaningful buffer that blocks renewals by Hizbullah or other extremists.
  • Operational flexibility: Advanced defensive arrays inside Israel for rapid response.
  • International cooperation: A multinational force that confers legitimacy and enforces on the ground.

Program components:

• • Demilitarized buffer (10–15 km) inside Lebanon

Control structure:

• • • U.S.-led multinational force: Oversees demilitarization and ensures the Lebanese government bars any renewal of terrorist activity.
    • Potential Arab partners:
      • Jordan: Training Lebanese forces to hold and maintain the area.
      • Egypt: Managing logistics facilities and engineering oversight.
      • UAE: Funding and controlled support for civilian projects.

Key features:

• • • No restoration of commanding ridgelines: Designate principal villages/areas as “no-rebuild on commanding ridges” to prevent return of terror groups.
    • Technological monitoring: Smart cameras, patrol UAVs, early-warning systems.
    • Ground obstacles: Build ground obstacles on selected terrain to prevent ground incursions into Israel akin to the Gaza October 7 model.
    • Building permits: Any civilian project requires joint approval by the Lebanese government under multinational supervision.
    • Central monitoring hub: Located near Naqoura, with direct access to multinational forces.

Multinational coordination and crisis management:

• • Border Multinational Coordination Center:
    • Located near Rosh Hanikra; includes representatives from the U.S., Lebanon, and Israel.
    • Responsible for incident management with the LAF.
  • Intelligence coordination:
    • A shared intelligence framework—Israeli advanced ISR fused with ground collection by the multinational force.
  • Civil support:
    • Emergency civil centers near Metula and Rosh Hanikra to support populations during escalations.
    • Controlled humanitarian resettlement aid for evacuated Lebanese villagers if needed.

Advantages:

• • Security and international prestige: U.S. and Arab participation boosts legitimacy.
  • Active defense: Israeli technology coupled with on-ground multinational presence.
  • Prevents terror re-entrenchment: Demilitarization and building limits block renewal.
  • Improves Lebanese stability: Supports Beirut’s control and provides civil assistance.

Risks:

• • Lebanese destabilization: Need rapid-response mechanisms for political shifts.
  • Problematic cooperation: Ensure long-term commitment by the multinational force.
  • Border breaches: Bolster advance intelligence arrays inside Israel.
  • The Shiite population: May return to the area, still supports Hizbullah ideology, and may be used to help resumption of terror infrastructure.
• Create a strong, effective multinational force (not a UN body): Replace UNIFIL with a new multinational force led by the U.S. and joined by states with an interest in regional stability (e.g., France, Britain, Germany, Gulf states). Give it a clear, robust mandate with enforcement powers, authority to use force, and unrestricted access across southern Lebanon. Its core missions:
  • Prevent any return of Hizbullah or other armed actors to the demilitarized zone.
  • Oversee dismantlement of remaining military infrastructure.
  • Assist the LAF in establishing sovereignty in the area.
  • Prevent arms smuggling into the zone.
  • Establish an efficient dispute-resolution and coordination mechanism with Israel and Lebanon.
• LAF deployment: The LAF deploys throughout the demilitarized zone as the sole Lebanese sovereign actor permitted to operate there, supported by the multinational force with equipment, training, and logistics.

Phase C: Long-Term Stabilization, Economic Development, and Gradual Easing (Condition-Based)

• Prove sustained stability and security: Only after a significant period (e.g., 5–10 years) of complete quiet, full demilitarization, and no hostile activity from southern Lebanon should certain easings be considered. This period is needed to build trust and prove Lebanon’s commitment.
• Economic incentives and development of southern Lebanon: In parallel with security stabilization, the international community, led by the U.S. and the EU, offers a significant economic aid package to develop southern Lebanon. Development provides a socioeconomic alternative for locals and reduces dependence on Hizbullah.
• Specific arrangements on disputed points: Through the coordination mechanism, address specific points of dispute along the border (e.g., Shebaa Farms/Mount Dov, Ghajar) based on international law and both sides’ security needs.
• Reassess Israeli aerial freedom of action: As stability consolidates and the LAF and multinational force prove capable of preventing threats, Israel’s aerial freedom over Lebanon can be gradually curtailed, while retaining responsive capability in case of grave violations.

International and Domestic Challenges to Implementing the Proposed Option

Implementing such an ambitious strategic vision entails complex challenges internationally and domestically:

1. Internal Lebanese resistance: Hizbullah and its political allies will vehemently oppose any move that harms their status and military power, potentially sabotaging implementation via political pressure, internal violence, or renewed fighting. Even a well-intentioned Lebanese government will struggle to garner broad backing for a plan that could be seen as capitulation to external dictates or an infringement of sovereignty (though the current situation is a far graver infringement).
2. Regional resistance, chiefly from Iran: Disarming Hizbullah is a severe strategic blow to Iranian interests. Tehran will use all its influence to thwart such a move and continue backing Hizbullah and other destabilizing actors.
3. Building broad international consensus and support: Creating a U.S.-led multinational force with a strong mandate and enforcement power requires agreement from key UN Security Council powers (U.S., U.K., France, and possibly Russia and China, which are more likely to demur). States must be persuaded to contribute troops and resources, and disagreements over mandate scope and use of force must be overcome.
4. Ensuring long-term U.S. commitment: U.S. leadership is essential but demands sustained political, military, and economic commitment, never guaranteed and dependent on U.S. domestic politics and perceived interests.
5. Logistical and budgetary hurdles: Standing up and operating a large, well-equipped multinational force and major economic-development programs in southern Lebanon require significant international funding and efficient management mechanisms.
6. Defining effective enforcement and sanction mechanisms: Pre-define responses to violations—by Hizbullah or by the Lebanese government (if non-compliant). International sanctions and an option for military response (by the multinational force or Israel) must be clear and agreed in advance.

Summary and Conclusions: Toward a New Era of Security in the North—From Vision to Reality

The strategic reality on the Israel–Lebanon border, revealed in full severity since October 7, demands a fundamental paradigm shift. Persisting with failed models such as UNSCR 1701 and UNIFIL in its current form is an invitation to the next disaster. This proposal addresses the roots of failure—Lebanon’s inherent weakness, the UN’s ineffectiveness, and Iran/Hizbullah’s central role in destabilization.

The premise that an Israeli victory in the current campaign can create an opportunity for change obligates Israel to craft a clear, long-term strategic vision. The proposed alternative, a phased framework featuring a broad demilitarized security zone, supervised by an effective U.S.-led multinational force, while preserving initial Israeli freedom of action, offers a path to address these complex challenges. It combines military strength, resolute diplomacy, and international commitment, recognizing the need for sustainable solutions grounded in real changes on the ground.

Implementing this vision will be difficult, as detailed above. It requires determined leadership in Israel, U.S. willingness to assume a leading role, and cooperation from key international actors. Above all, it requires understanding that there are no quick fixes: durable security on the northern border will come only through sustained, multi-dimensional effort and the demonstration of strategic resolve. The repeated failures of the past must serve as a warning, and as a source of insight for building a safer future for Israel’s northern residents and the state as a whole. The shift from temporary stabilization to sustainable security demands readiness for bold moves and a deep conceptual change.