SOUTHEAST ASIA — The United States and Indonesia announced a defense cooperation partnership on April 14 that includes expanded U.S. access to Indonesian airspace and a focus on security around the Strait of Malacca. President Prabowo Subianto approved the proposal granting wider access to Indonesian airspace.

Indonesia's archipelago sits astride key international sea routes, and the Strait of Malacca functions as a chokepoint for global shipping and trade. The region has seen increasing military attention from outside powers in recent years, with the U.S. expanding its presence through base access and naval deployments and China expanding its presence through its port network and naval buildup. The Andaman and Nicobar Islands, near the western approaches of the strait, provide India with a strategic presence in the region. There is no clear indication that the increased military presence around the strait is affecting commercial shipping.

The strait stretches approximately 900 kilometers from the Malay Peninsula to the Indonesian island of Sumatra and is the shortest sea route connecting the Indian Ocean to the South China Sea and the Pacific Ocean. Its narrowest point, the Phillips Channel near Singapore, is about 2.8 kilometers wide. Almost 24% of global seaborne trade volume flows through the strait, including 45% of the world's seaborne oil, more than 25% of all cars traded internationally, and 23% of dry bulk cargo such as grains and soybeans. A portion of European imports of electronics, consumer products, machinery, and industrial goods passes through the strait in sea containers.

Singapore, located at the southern entrance of the strait, is the second-busiest container port in the world, the busiest container transshipment hub, and the world's largest ship refuelling hub, handling over 40 million containers annually. Port Klang in Malaysia ranks among the world's top ten container ports and handles 14 million containers annually.

The Sunda and Lombok Straits, both within Indonesian territory, are alternative routes, though neither is a straightforward substitute. Rerouting through them adds about 1,000 to 1,500 nautical miles, three to five days at sea, higher fuel costs, and the loss of Singapore's refueling infrastructure. The Torres Strait near Papua New Guinea is too shallow for commercial vessels with a draft over 12 meters, and a detour around the Australian continent adds another 10 to 15 days of transit time.

In 2003, China's then-president Hu Jintao coined the term "Malacca dilemma" to describe China's strategic exposure from reliance on the strait. Between 75% and 80% of China's imported oil passes through it, against total imports of roughly 11 million barrels per day. Pipelines from Kyaukpyu in Myanmar to Yunnan province bypass the strait with a capacity of about 440,000 barrels per day, and Central Asian oil and gas pipelines supply about 10% of China's imported oil. Gwadar Port in Balochistan, Pakistan, developed largely with Chinese investment as part of the China-Pakistan Economic Corridor, is planned to link to Xinjiang via road, rail, and energy infrastructure, but the corridor is only partially developed, with completion affected by difficult terrain and security challenges in parts of Pakistan. Rail freight corridors connect China to Europe, avoiding maritime chokepoints, but are more expensive than shipping and have limited capacity. Arctic shipping routes along Russia's northern coast shorten the distance between Asia and Europe but remain seasonal and marginal in global trade.