US aims to keep Chinese navy guessing with new missile system

The Navy-Marine Expeditionary Ship Interdiction System, or Nmesis, is an antiship missile launcher mounted on a remote-controlled truck. The dumbbell-shaped islet where it landed lies just 120 miles south of Taiwan.

For the Marines, the Nmesis’s flight to Batan was a key test in a high-stakes retooling aimed at readying the military’s rapid-response force for a war with China in some of the world’s most strategic, but increasingly tense, waterways.

The prospect of an armed conflict with China—whether over Taiwan, the self-governed democracy Beijing claims as its own, or the contested shipping lanes of the South China Sea—has the U.S. playing catch-up. While American forces were bogged down in Iraq and Afghanistan, China built up the world’s biggest navy and a formidable arsenal of missiles aimed at making swaths of the Pacific off-limits to its adversaries.

The Nmesis—pronounced “nemesis"—was designed to erode that lead. It takes advantage of natural chokepoints like Batan to raise the cost of access for Chinese warships. Initially built to be launched from ships, the Norway-made Naval Strike Missiles the Nmesis fires can sink vessels some 115 miles away, skimming the water and adjusting their trajectory to follow and hit a moving target.

With the Nmesis, Marines can now shoot these high-precision missiles from land, including from remote, mountainous islands like Batan, where launchers are far easier to conceal than on the open water. The main vehicle carrying the missiles is unmanned. Its operators work from a distance, based in two support vehicles that place them outside the line of fire of anyone trying to take out the launchers.

The Nmesis’ mere presence on strategic islands in the Pacific complicates decision-making for adversaries, who have to weigh the threat it poses for any vessel that may find itself within striking distance, said Col. John Lehane, the commander of the Hawaii-based Marine regiment that deployed the system to Batan late last month as part of an annual exercise.

“Once you put it on the ground, it is there. It can move around. It is hard to find," Lehane said.

The Nmesis’s antiship capabilities give it an edge over other land-based missile systems, such as the M142 High Mobility Artillery Rocket System, or Himars, which helped transform the battlefield in Ukraine but has struggled to hit moving targets at sea, Lehane said.

Rommel Ong, a former vice commander of the Philippine navy and now a senior research fellow at the Ateneo School of Government in Manila, likened the Nmesis’ presence on islands in the Western Pacific islands to a “shell game."

“You keep the other side guessing and that creates the uncertainty and in a way that creates the deterrent effect," he said.

Lehane’s 3rd Marine Littoral Regiment was the first Marine unit to take delivery of the new system late last year. The Nmesis is a centerpiece of a broader overhaul of the Marines aimed at making the force more agile, able to swoop into action even after a conflict has already erupted.

The Philippines, America’s oldest treaty ally in Asia, is a key part of that new push. The government of President Ferdinand Marcos Jr. has given the U.S. military access to more bases, on which it can build facilities, pre-position equipment and refuel and maintain aircraft and vessels.

Since the U.S. has no permanent troops based in the Philippines, Washington would have to airlift fighters and weapons to small, hard-to-access islands, under the threat of enemy fire.

Extensive drills mean some U.S. troops now rotate through Philippine bases for much of the year. That not only improves coordination with the Armed Forces of the Philippines, but also allows Marines and Air Force pilots to get more familiar with the topography of the Pacific theater. On practice flights and reconnaissance missions, they scope out mountains and other features that could serve as cover.

“We get really low and hide," said Capt. Benjamin Dorsey of the 39th Airlift Squadron, which moved the Nmesis to Batan.

Lehane said the successful deployment of the Nmesis should signal to potential adversaries that the Marines’ island fighters are ready for combat.

“A lot of folks are still perceiving our unit as experimental and it’s absolutely not experimental," he said. “The most important thing is to get folks accustomed to the fact that where you see 3rd Marine Littoral Regiment, you should expect that there are Nmesis with us."

Write to Gabriele Steinhauser at Gabriele.Steinhauser@wsj.com