Security Council

✦ Topic A

Evaluating the World’s Nuclear Arsenal, Including Old Weaponry & Uranium Refining Facilities

1. Introduction & Background

Nuclear weapons have been a major international security concern since 1945. During the Cold War, the United States and Soviet Union developed large nuclear arsenals, creating an arms race based on nuclear deterrence.

The main international agreement addressing nuclear proliferation is the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). It entered into force in 1970 and aims to prevent the spread of nuclear weapons, promote peaceful nuclear energy, and encourage nuclear disarmament. It has 191 States Parties.

Nine states are generally recognized as possessing nuclear weapons: United States, Russia, China, France, United Kingdom, India, Pakistan, Israel, and North Korea. In 2025, the global inventory was estimated at approximately 12,241 warheads.

The issue also involves aging and retired weapons. Nuclear weapons and their delivery systems require maintenance, secure storage, replacement, or dismantlement. Retired weapons create challenges involving the safe management of nuclear materials.

Another concern is uranium enrichment. Enriched uranium has peaceful uses, including nuclear energy, but higher levels of enrichment can also be used in nuclear weapons. The International Atomic Energy Agency (IAEA) therefore monitors nuclear activities through safeguards and inspections.

Nuclear arms control has also become more uncertain following the expiration of New START between the United States and Russia on 5 February 2026.

2. Key Issues & Challenges

A Nuclear Arsenal Size

The world continues to possess thousands of nuclear weapons, with the United States and Russia holding the majority. China is also expanding its nuclear capabilities. The international community must consider how arsenals can be reduced without creating new security risks.

B Aging and Retired Weapons

Older weapons require maintenance, replacement, or dismantlement. States must safely store and manage nuclear materials while preventing theft, accidents, or unauthorized access.

C Uranium Enrichment

Uranium enrichment can support peaceful nuclear programs but can also create proliferation concerns. The challenge is balancing states' right to peaceful nuclear technology with the need to prevent nuclear weapons development.

D Verification and Transparency

Effective arms control requires reliable information, inspections, and monitoring. Disagreements can occur over access to facilities, inspections, and undeclared activities.

E Future Arms Control

The expiration of New START has removed binding strategic limits between the United States and Russia. The Comprehensive Nuclear-Test-Ban Treaty (CTBT) has also not entered into force. Meanwhile, the Treaty on the Prohibition of Nuclear Weapons (TPNW) seeks to prohibit nuclear weapons among its parties.

3. International Perspectives

Nuclear-weapon states generally argue that nuclear weapons contribute to national security through deterrence while participating to varying degrees in arms-control agreements.

Non-nuclear-weapon states generally emphasize non-proliferation and nuclear disarmament.

The IAEA focuses on monitoring nuclear activities and verifying peaceful use, while the United Nations provides the wider diplomatic framework.

The main disagreements concern nuclear deterrence, disarmament, modernization, uranium enrichment, and verification.

4. Previous International Action

• NPT: Prevents nuclear proliferation and promotes peaceful nuclear cooperation and disarmament.
• IAEA Safeguards: Monitor nuclear materials and activities.
• CTBT: Prohibits nuclear explosions but has not entered into force.
• TPNW: Prohibits nuclear weapons for its participating states.
• New START: Limited US and Russian strategic nuclear weapons until its expiration in 2026.

✦ Topic B

Addressing the Thailand-Cambodia Border Conflict

1. Introduction & Background

Thailand and Cambodia have experienced territorial disagreements for more than a century. Some disputes originate from border arrangements established during French colonial rule.

The 1904 Franco-Siamese Treaty helped establish parts of the border between French Indochina and Siam, now Thailand. Disagreements over maps and boundaries later contributed to tensions surrounding the Temple of Preah Vihear.

In 1962, the International Court of Justice (ICJ) ruled that the Temple of Preah Vihear was located in Cambodian territory and ordered Thailand to withdraw its forces from the area. In 2013, the Court clarified the territorial scope of its earlier judgment.

Tensions increased after the temple became a UNESCO World Heritage Site in 2008, with armed clashes occurring in frontier areas.

The conflict escalated significantly in 2025, resulting in casualties, infrastructure damage, and large-scale displacement. ASEAN called for a ceasefire and negotiations. Fighting resumed in December, leading to further humanitarian concerns.

On 27 December 2025, Thailand and Cambodia reached a ceasefire through the General Border Committee process, including measures for de-escalation and verification.

2. Key Issues & Challenges

A Territorial Disputes

The main disagreement concerns the precise location and interpretation of sections of the border. Historical treaties, maps, and different interpretations have contributed to competing claims.

B Military Escalation

Military forces stationed near disputed areas increase the risk that border incidents could develop into larger conflicts. The 2025 fighting demonstrated this risk through the use of heavy weapons and air attacks.

C Civilian Protection

The conflict has displaced civilians and damaged infrastructure. During the July 2025 fighting, more than 172,000 people were displaced in Cambodia according to UN reporting.

The protection of civilians and humanitarian access must therefore remain priorities.

D Ceasefire Implementation

Thailand and Cambodia have used bilateral committees, ASEAN diplomacy, ceasefire agreements, and observer mechanisms. However, maintaining a ceasefire requires cooperation, communication, and effective monitoring.

E Regional Stability

Continued conflict could affect wider Southeast Asian stability. ASEAN has encouraged peaceful settlement, while the United Nations has called for de-escalation, civilian protection, and renewed dialogue.

3. International Perspectives

Thailand emphasizes territorial security, sovereignty, border management, and bilateral negotiations.

Cambodia emphasizes territorial sovereignty, border demarcation, and implementation of existing agreements.

ASEAN focuses on regional stability, dialogue, and peaceful dispute settlement. Its ASEAN Observer Team can assist with monitoring and verification.

The United Nations focuses on international peace and security, civilian protection, humanitarian assistance, and peaceful conflict resolution.

The ICJ has played an important role through its 1962 and 2013 decisions concerning the Temple of Preah Vihear.

4. Previous International Action

• ICJ 1962: Recognized Cambodian sovereignty over the Temple of Preah Vihear.
• ICJ 2013: Clarified the territorial scope of the 1962 judgment.
• ASEAN 2025: Called for ceasefires, restraint, and negotiations.
• ASEAN Observer Team: Supported monitoring and verification.
• December 2025 Agreement: Established a ceasefire and de-escalation measures.

Despite these efforts, disagreements over border demarcation, military positions, and ceasefire implementation remain.