Geography · 10th Grade · Political Geography and Global Power · Weeks 28-36

Maritime and Land Border Disputes

Investigating the primary causes of maritime and land border disputes globally.

• Common Core State Standards
• C3: D2.Geo.5.9-12
• C3: D2.Civ.14.9-12

About This Topic

Border disputes arise when two or more states claim the same territory or contest the precise location of a boundary. For US students, this topic moves from abstract political geography toward geopolitical strategy and current events. The South China Sea dispute involves six claimants and is one of the most strategically significant maritime conflicts in the world, touching on freedom of navigation, energy resources, and the broader US-China rivalry. The US-Mexico border presents contrasting themes around migration policy, wall construction, and the ecological and economic consequences of hardened borders.

Maritime disputes are especially complex because the ocean was not traditionally divided into national territories. The UN Convention on the Law of the Sea established a framework for exclusive economic zones and continental shelf rights, but states frequently dispute where measurements begin and whether islands, artificial reefs, or constructed features qualify as territory generating maritime rights.

Climate change adds a new dimension to border disputes. Rising sea levels threaten low-lying island states with potential submersion, raising questions about whether states that lose their land territory retain sovereignty and maritime rights. Climate-induced migration may also intensify pressure on land borders as populations move in response to resource scarcity. Active learning approaches, including structured simulations of border negotiations, are productive for this topic because students must weigh competing legal, geographic, and ethical claims simultaneously.

Key Questions

1. Analyze the primary causes of maritime border disputes in the South China Sea.
2. Explain how walls and fences affect the ecosystems and economies of border regions.
3. Predict the future of border disputes in a world facing climate-induced migration.

Learning Objectives

• Analyze the competing claims and legal arguments in the South China Sea maritime dispute.
• Evaluate the ecological and economic impacts of border walls and fences on regions like the US-Mexico border.
• Compare and contrast the causes and consequences of maritime versus land border disputes.
• Predict how climate change and resulting migration patterns might reshape future land border disputes.
• Synthesize information from legal texts, geographic data, and news reports to form an argument about resolving a specific border dispute.

Before You Start

Introduction to International Relations

Why: Students need a basic understanding of how nation-states interact and the concept of national interest to grasp the motivations behind border disputes.

Physical Geography: Landforms and Oceans

Why: Knowledge of coastlines, islands, and oceanographic features is essential for understanding maritime boundary claims.

Concepts of Sovereignty and National Borders

Why: Students must understand what a border represents and the idea of state sovereignty before analyzing disputes over them.

Key Vocabulary

Exclusive Economic Zone (EEZ)	A maritime zone extending 200 nautical miles from a country's coast, within which the country has sovereign rights to explore and exploit natural resources.
Territorial Sea	A belt of coastal waters that extends at most 12 nautical miles from the baseline of a coastal state, over which the state has sovereignty.
UN Convention on the Law of the Sea (UNCLOS)	An international agreement that establishes the rights and responsibilities of nations in their use of the world's oceans, including defining maritime boundaries.
Sovereignty	The supreme authority within a territory, including the right to govern and control its own territory and population.
Climate-induced migration	The movement of people from one place to another due to the impacts of climate change, such as sea-level rise, desertification, or extreme weather events.

Watch Out for These Misconceptions

Common Misconception

The country with the largest military presence in a disputed zone has the strongest legal claim.

What to Teach Instead

Military presence and legal claim are separate questions. UNCLOS and international arbitration rulings are based on geography, historical use, and treaty law, not on which state controls territory by force. The 2016 Permanent Court of Arbitration ruling against China's nine-dash line in the South China Sea illustrates that legal and military realities can diverge significantly.

Common Misconception

Border walls and fences primarily affect human migration and have little other impact.

What to Teach Instead

Physical border barriers affect wildlife corridors, water flow, and cross-border economic activity in addition to human movement. The US-Mexico border infrastructure has fragmented habitats for jaguars, pronghorns, and other species with large ranges. Understanding these ecological dimensions requires spatial thinking about what borders actually do to landscapes.

Common Misconception

Border disputes are primarily a problem in developing regions and rarely affect wealthy countries.

What to Teach Instead

Border disputes involve countries at all income levels. Norway and Russia settled a maritime boundary dispute in the Barents Sea in 2010. The US and Canada have an ongoing dispute over the Northwest Passage's legal status. Japan and several neighbors dispute island territories. Conflict potential is tied to resource value and strategic significance, not national wealth.

Active Learning Ideas

Map Analysis: South China Sea Claims

Students examine an annotated map of the South China Sea showing overlapping national claims, island features, and shipping lanes. In pairs, they identify the geographic basis for each claim, discuss what resources are at stake, and analyze why the dispute has been difficult to resolve through international arbitration.

25 min·Pairs

Simulated Negotiation: Maritime Boundary Dispute

Assign groups to represent different claimant states in a South China Sea scenario. Each group reviews their assigned country's geographic position and strategic interests, then participates in a structured negotiation round. The class debriefs on which geographic arguments proved most persuasive and why consensus was difficult to reach.

45 min·Small Groups

Think-Pair-Share: Walls, Fences, and Ecosystems

Present data on the ecological and economic effects of the US-Mexico border wall on wildlife corridors and cross-border communities. Partners discuss the tradeoffs between border security goals and environmental costs, then share their analysis with the class to build a broader discussion about unintended consequences of border hardening.

20 min·Pairs

Real-World Connections

• International lawyers and diplomats engage in complex negotiations, often using simulations and legal precedent, to resolve disputes over fishing rights and resource extraction in areas like the South China Sea.
• Border patrol agents and environmental scientists work together to monitor the effects of border infrastructure, such as the wall along the US-Mexico border, on wildlife migration patterns and local water resources.
• Urban planners in coastal cities like Miami are developing strategies to manage potential sea-level rise and its impact on property lines and infrastructure, anticipating future challenges to existing boundaries.

Assessment Ideas

Discussion Prompt

Pose the question: 'Given the principles of UNCLOS, what are the strongest legal arguments for China's claims in the South China Sea, and what are the strongest counterarguments from neighboring nations?' Facilitate a debate where students represent different claimant states.

Exit Ticket

Ask students to write two sentences explaining one way climate change could lead to new land border disputes, and one sentence describing a potential economic consequence of a hardened border.

Quick Check

Provide students with a short case study of a fictional border dispute. Ask them to identify: 1) whether it is primarily a land or maritime dispute, and 2) one key factor (e.g., resources, historical claims, geography) driving the conflict. Review answers as a class.

Frequently Asked Questions

What causes maritime border disputes

Maritime disputes typically arise from overlapping exclusive economic zone claims, competing interpretations of which geographic features generate maritime rights, and the high value of offshore resources including oil, natural gas, and fisheries. UNCLOS gives states 200-nautical-mile EEZ rights from their baselines, but when states are close together their zones overlap, requiring negotiation or arbitration. The legal status of islands, reefs, and artificial structures is especially contested because it determines the extent of surrounding maritime rights.

Why is the South China Sea disputed

China, Vietnam, the Philippines, Malaysia, Brunei, and Taiwan all claim portions of the South China Sea based on historical use, geographic proximity, and island sovereignty claims. The area contains significant oil and gas deposits, some of the world's busiest shipping lanes, and rich fishing grounds. China's nine-dash line claim covers approximately 90 percent of the sea and has been ruled inconsistent with UNCLOS by an international tribunal, a ruling China does not recognize.

How do land border disputes start

Land border disputes typically originate from ambiguous boundary treaties, colonial-era demarcation errors, shifts in physical features used as boundaries, or competing historical claims to the same territory. Post-colonial states often inherited borders drawn without precise surveying, leaving gaps and overlaps that emerge as disputes when resources are discovered or populations expand into frontier areas. Strategic or symbolic value of territory can also motivate disputes independent of economic considerations.

How does active learning help students analyze border disputes

Border disputes involve multiple overlapping legal principles, geographic realities, and national interests that cannot be understood through lecture alone. Simulated negotiations require students to reason from a specific country's geographic position and strategic interests, making the spatial dimensions of the dispute concrete. Debriefing after simulations helps students identify patterns across cases and develop analytical frameworks they can apply independently to new disputes.