The diverse nations bordering the Pacific Ocean, from the coral reefs of Southeast Asia to the coastal rainforests of Latin America, grapple with significant and often interconnected environmental and criminal challenges, further complicated by the growing influence of state actors like China. These diverse countries, collectively known as the Pacific Rim, face existential threats ranging from illegal logging, fishing, and resource exploitation; the impacts of climate change, transnational organized crime; as well as political and security concerns. To confront these multifaceted issues, these nations are increasingly collaborating to enhance their collective capabilities and build interoperability.
Transcending borders
The U.S. military, primarily through U.S. Indo-Pacific Command (INDOPACOM) and U.S. Southern Command (SOUTHCOM), has become a key partner in addressing these issues. While their primary areas of operations differ, their missions to enhance security and counter the activities of transnational criminal organizations that operate across regions and the strategic interests of external state actors intersect. This overlap allows Pacific Rim nations to leverage the distinct expertise of both commands through targeted combined training and exercises, bolstering their capacity to address shared security concerns.
SOUTHCOM frequently conducts exercises tailored to the specific threats of the region, such as the annual UNITAS multilateral maritime exercise, which includes Pacific-facing Latin American partners like Colombia, Peru, and Chile and often counts on the participation of Indo-Pacific nations like Australia. These exercises focus on enhancing capabilities in areas like counternarcotics operations, humanitarian assistance and disaster response, and maritime interdiction — all directly relevant to the environmental security challenges and transnational crime these nations face along their Pacific coasts.
INDOPACOM, while focused on the Indo-Pacific, also engages with Latin American partners on the Pacific coast through specific security cooperation initiatives and exercises. These engagements often bring expertise in maritime domain awareness, countering illegal trafficking, and addressing the impacts of climate change on coastal security. The Command’s experience in working with a diverse set of Pacific nations facing similar challenges provides valuable lessons and perspectives for Latin American partners.
Partners integrated and prepared
One significant multilateral exercise that underscores the U.S. commitment to the region is the Rim of the Pacific (RIMPAC) exercise. Held biennially in and around the Hawaiian Islands, RIMPAC is the world’s largest international maritime exercise. It brings together naval forces from across the Pacific Rim, including nations from North and South America, Asia, and Oceania. Its last edition gathered 40 ships, three submarines, more than 150 aircraft, and 25,000 service members from 29 nations. While INDOPACOM leads RIMPAC, the participation of Latin American countries highlights the interconnectedness of Pacific security issues.
For instance, in 2024, for the first time in RIMPAC history, a member of the Chilean Navy, Commodore Alberto Guerrero, served as deputy commander of the exercise’s Combined Task Force (CTF). “In this modern world, everything we do in the Pacific matters. So, many nations come together [for RIMPAC] to protect civilians and communications, to protect free trade, open seas, which is an added value to prosperity and security,” Commodore Guerrero said during an interview with Hawaii’s KHON-TV to highlight the exercise. “To be leading this incredible group of men and women is a privilege and a true honor.”
In addition to Chile, other Latin American nations like Colombia, Mexico, and Peru have also sent naval assets to past iterations of RIMPAC, participating in a wide range of drills, including maritime security operations, amphibious landings, and live-fire exercises. These exercises provide a crucial platform for these nations to enhance their interoperability with the U.S. and other partner nations’ security forces from the Pacific Rim.
“We are honored to have participated in such a comprehensive exercise,” said Peruvian Navy Lieutenant Junior Grade Gonzalo Hernández, who took part in RIMPAC 2024. “The shared experiences and knowledge gained here are invaluable, and we look forward to applying these lessons to improve our […] capabilities.”
For U.S. Navy Vice Admiral John Wade, commander of U.S. 3rd Fleet and RIMPAC 2024 CTF commander, that’s what it’s all about. “Working together as a team, working toward a common goal, for peace and stability,” Vice Adm. Wade said at the conclusion of the exercise. The main objectives, he added, are “to build and enhance relationships, to improve our interoperability […] to ensure that we are more prepared to respond to a natural disaster, to deter conflict, and then if required to respond to aggression.”
Combating maritime crimes
One recurring issue these exercises address is illegal, unreported, and unregulated (IUU) fishing, which not only depletes vital fish stocks but is also often linked to other illicit activities, including drug and human trafficking. China’s vast and rapidly expanding distant-water fishing fleet is the top IUU fishing offender globally, and its aggressive practices not only exacerbate ocean depletion but also pose direct challenges to the navies and maritime law enforcement agencies of other nations in the region. The sheer scale of the Pacific makes monitoring and enforcement a significant challenge for many.
“A regional threat with a major impact is China’s illegal, predatory fishing […],” Retired General Olswaldo Jarrin Román, former Defense minister of Ecuador, wrote in a 2022 report for the William J. Perry Center for Hemispheric Defense Studies. “IUU fishing affects the entire South American Pacific region from Chile, Peru, Ecuador, and Colombia, an area of immense fishing wealth, where, in the vicinity of the Galapagos, not only criminal predatory activity take place, but also threatens endangered species.”
In 2017, the Ecuadorian Navy intercepted and captured the Chinese fishing vessel Fu Yuan Yu Leng inside the Galapagos Marine Reserve with 300 metric tons of shark fins, underscoring the fishing capacity of a single vessel. In the Indo-Pacific region, China’s fishing fleet also makes frequent audacious incursion into foreign exclusive economic zones (EEZs), in part due to China’s claims in the South China Sea.
These exercises, including RIMPAC and those directly coordinated by SOUTHCOM, often involve naval assets, aerial surveillance, and the deployment of special forces, providing invaluable opportunities for partner nations to learn from each other’s expertise and to operate alongside their counterparts from other countries. This fosters greater interoperability and a shared understanding of the complex security landscape.
China’s threat
Beyond environmental crime, the growing assertiveness of China in the Pacific Rim adds a significant layer of complexity. China’s increasing economic and strategic influence has led to concerns about its impact on established international norms, the potential for exacerbating resource competition, and the creation of new security dilemmas. Its expanding naval presence and the activities of its distant-water fishing fleet, which China uses as a tool for maritime power and territorial assertion, raise questions about sovereignty, sustainability, and the rule of law within the EEZs of many Pacific Rim nations, both in Asia and Latin America.
This assertiveness is vividly demonstrated by China’s extensive territorial claims in the South China Sea, where it has engaged in aggressive militarization of disputed features, challenging international law and freedom of navigation. In addition, China’s reliance on “gray zone” tactics, such as employing its vast maritime militia to harass other nations’ vessels, and its rapid military modernization underscore a deliberate strategy to alter the regional security landscape.
“China continues to pursue unprecedented military modernization and increasingly aggressive behavior,” U.S. Navy Admiral Samuel Paparo, INDOPACOM commander, said in a U.S. House Armed Services Committee testimony in April 2025. “China employs a multifaceted approach combining military pressure, cognitive and cyber operations, and economic coercions.”
In this context, combined military training and exercises, such as RIMPAC, UNITAS, PANAMAX, as well as other initiatives, take on added importance. They serve not only to enhance the participating nations’ capabilities to address environmental crimes and humanitarian crises but also to foster interoperability and build a collective security posture that can serve as a deterrent to actions that undermine regional stability, including those posed by China’s growing influence.
Reliable partners
These engagements between the United States and partner nations from the region and afar, provide reliable security partners, and reinforce the sovereignty and independence of participating countries. Combined exercises often include components focused on humanitarian assistance and disaster relief, while some are primarily centered on aid, highlighting the U.S. commitment beyond purely security cooperation.
For instance, each year INDOPACOM launches its Pacific Partnership mission, which focuses on strengthening partnerships, enhancing disaster response capabilities, and providing medical and engineering assistance to host nations. The USNS Mercy serves as platform for these efforts, while the embarked medical personnel from the U.S. and partner nations enable the delivery of comprehensive healthcare services. Chilean service members have participated on several occasions to this mission.
Likewise, sister ship USNS Comfort, frequently deploys to Latin America and the Caribbean for Continuing Promise (CP), a similar humanitarian mission. Since its 2007 inception, CP medical personnel have treated more than 600,000 people, and performed nearly 8,000 surgeries.
Concerted effort
The scale and multinational participation in exercises like RIMPAC and UNITAS send a clear signal of the collective commitment of Pacific Rim nations to a free and open Pacific, based on the rule of law. By training together, these nations enhance their ability to operate seamlessly, share information, and present a unified front in the face of challenges that could potentially destabilize the region. The tangible outcomes of these combined efforts can be seen in increased seizures of narcotics, illegal timber, more effective patrols against maritime crime, and improved coordination in disaster response.
The participation of Indo-Pacific, Asian, and Oceanian nations in SOUTHCOM exercises and Latin American countries in INDOPACOM engagements underscores a unified approach to security across the entire Pacific, recognizing that challenges posed by state actors can have far-reaching implications. This unity is increasingly seen as crucial in navigating the complexities introduced by China’s growing influence.
As the challenges in the Pacific Rim continue to evolve, and as the strategic landscape becomes increasingly complex, the role of combined training and security cooperation between the United States and its Pacific partners is likely to become even more critical, requiring sustained commitment and cooperation.
Perhaps U.S. Navy Admiral Alvin Hosley, SOUTHCOM commander, best captured this commitment in his November 2024 inaugural address. “To be clear, partnerships are our best deterrence to counter shared security and economic concerns,” Adm. Hosley said. “We will always be there for like-minded nations who share our values, our democracy, our rule of law, our human rights.”
