The Strait of Malacca, near where 10 U.S. sailors are missing after their vessel, the USS John S. McCain, collided Sunday with an oil tanker, has historically been one of the world’s busiest shipping routes and chokepoints—and growing traffic in the waterway has resulted in recent warnings of the increased risk of accidents.

The strait connects the Pacific and Indian Oceans. Many of the world’s largest economies, which are now concentrated in the Asia-Pacific region, use the channel for trade with the energy-rich Middle East and resource-rich Africa. The strait is one of the world’s busiest: Nearly 100,000 vessels pass through it each year, accounting for about one-quarter of the world’s traded goods.

But geography, which makes the strait especially crucial for global commerce, is also what makes the Strait of Malacca dangerous. It remains one of the world’s narrowest straits: 1.5 nautical miles, or about 1.7 miles on land, at its narrowest point, the Phillips Channel, near Singapore, making it a particularly perilous place for ships. Last year, officials from Indonesia, Malaysia, and Singapore, the countries surrounding the strait, agreed to take joint steps to reduce potential accidents. There were 60 such accidents in 2015—a number that is expected to grow as traffic through the strait increases each year.

Sunday’s collision occurred in waters claimed by both Malaysia and Singapore, Zulkifili Abu Bakar, the director of the Malaysian Maritime Enforcement Agency director, said. Bloomberg News reported that the oil tanker involved in the collision, the Alnic MC, was chartered August 17 to ship petroleum from Southeast Asia to the Far East. There was no oil pollution caused by the collision, Bloomberg said.

Accidents aren’t the only hazard in the Strait of Malacca: For years, it has been a hub for piracy—a phenomenon that saw a marked increase in the 2000s. Cooperation among regional navies has stemmed this problem, however. Haze from regional forest fires has resulted in poor visibility for vessels sailing in the strait; the region’s weather is also a factor in some accidents.

The Strait of Malacca has strategic importance, too: China, the dominant Asian power, is heavily reliant on the Middle East for its energy needs; about 25 percent of oil shipped between the Middle East and Asia passes through the strait—a figure that has steadily increased as China and other regional powers grow in population and wealth. Any blockade of the strait would result not only in China being cut off from its energy supplies in the Middle East, but also from raw material from Africa, where China has invested billions of dollars in mining and infrastructure projects.

The Energy Information Administration (EIA), the data arm of the U.S. Department of Energy, said blockage of the strait would force nearly half of the world’s shipping fleet to reroute around the Indonesian archipelago. “Rerouting would tie up global shipping capacity, add to shipping costs, and potentially affect energy prices,” the EIA said.

It’s this strategic importance that partly explains the continued presence of the U.S. Seventh Fleet in Japan. The U.S., while providing security guarantees for its regional allies—Taiwan (against a Chinese invasion), South Korea and Japan (against North Korean aggression), as well as its southeast Asian allies (against Chinese territorial claims in the South China Sea)—maintains its largest forward-deployed U.S. fleet, the Seventh Fleet, in Yokosuka, Japan. The presence of the fleet in the region is a reminder of longstanding U.S. interests in the region: The Seventh Fleet took part in the Korean and Vietnam Wars, as well as the liberation of Bangladesh, and the Gulf War.

China, realizing its dependence on the strait, is developing alternate routes via Sri Lanka and Pakistan. In 2013, Beijing also commissioned a gas pipeline from Myanmar that is now operating at full capacity, according to the EIA. Some of those other projects, though, are expected to take years—or decades—to complete. Until then, the Strait of Malacca will likely remain the preferred shipping route from the Indian Ocean to the Pacific (traffic is expected to double over the next decade)—and given the volume of trade and of vessels passing the chokepoint—the site of potentially more accidents.