Rim of the Pacific Exercise (RIMPAC)

The Rim of the Pacific Exercise (RIMPAC) is the world’s largest multinational maritime exercise, held biennially in and around the Hawaiian Islands and Southern California. First conducted in 1971, it was originally designed to enhance naval cooperation between the United States, Canada, Australia, and other Pacific allies during the Cold War. Over the decades, it has expanded significantly, with participation growing to over 25 nations, dozens of warships, submarines, aircraft, and thousands of personnel. Led by the U.S. Pacific Fleet (PACFLT), the exercise fosters interoperability, joint operational capabilities, and coalition readiness in areas such as naval warfare, amphibious operations, humanitarian assistance, and maritime security.

RIMPAC holds strategic significance as a deterrent demonstration of allied naval power and a proving ground for multinational military coordination. It allows partner nations to practice real-world scenarios ranging from anti-submarine warfare and missile defense to disaster relief operations and freedom of navigation exercises. The exercise also serves as a diplomatic tool, reinforcing alliances and partnerships across the Indo-Pacific. While typically inclusive, RIMPAC has at times been used to signal political tensions, as seen in China’s exclusion from recent iterations due to its militarization of the South China Sea. As regional security dynamics evolve, RIMPAC remains a cornerstone of U.S.-led defense cooperation in the Pacific, ensuring that allied forces can operate together effectively in times of crisis or conflict.

Key Training Areas & Capabilities Refined

Since its inception, RIMPAC has evolved into a comprehensive naval warfare and security exercise, incorporating a wide range of combat, humanitarian, and operational drills. Below is a list of specific capabilities and scenarios that RIMPAC nations rehearse, refine, implement, and test:

• Surface Warfare (SUW) — Live-fire missile engagements, anti-ship operations, and naval gunnery exercises.

• Anti-Submarine Warfare (ASW) — Sonar tracking, submarine hunting tactics, and simulated undersea battles.

• Mine Countermeasures (MCM) — Identification, neutralization, and removal of naval mines.

• Electronic Warfare (EW)– Jamming, deception tactics, and counter-electronic threats.

• Ballistic Missile Defense (BMD) — Testing integrated Aegis missile defense systems against simulated missile threats.

• Air Defense Operations — Coordinated fighter, bomber, and naval air response drills.

• Carrier Strike Group (CSG) Operations — Launch and recovery of carrier-based aircraft, power projection, and coordinated fleet movements.

• Amphibious Assaults — Beach landings with mechanized and aerial support.

• Maritime Prepositioning Force (MPF) Operations — Rapid deployment of combat-ready forces from sea to shore.

• Joint Logistics Over-the-Shore (JLOTS) — Sustainment of forces in areas with limited port infrastructure.

• Multinational Command & Control (C2) Drills — Integrating different national military doctrines into a unified structure.

• Combined Task Force Operations — Coordinated missions with ships, aircraft, and ground forces from multiple nations.

• Data-Sharing & Secure Communications — Testing encrypted networks for real-time intelligence-sharing among allies.

• Mass Casualty Evacuations (MASCAL) — Large-scale medical response to simulated disasters.

• Search & Rescue (SAR) Missions — Coordinated efforts for maritime and aerial recovery operations.

• Emergency Aid Distribution — Training in logistics for food, water, and medical supply distribution.

• Cyber Warfare Exercises — Simulating electronic attacks on naval and communication systems.

• Space-Based Coordination — Testing satellite communication and surveillance integration into naval operations.

• Unmanned Surface and Underwater Vehicles (USVs & UUVs) — Autonomous vessel operations and reconnaissance.

• Swarm Drone Tactics — Use of coordinated drone attacks in maritime combat scenarios.

• AI-Assisted Decision-Making — Testing artificial intelligence for logistics, targeting, and threat assessments.

Lessons from RIMPAC have directly influenced real-world operations, such as:

• Counter-piracy missions off the coast of Somalia.
• Disaster relief efforts following tsunamis, hurricanes, and earthquakes.
• Naval deterrence strategies in the South China Sea and Indo-Pacific.