WASHINGTON — As China expanded the reach of its weapons throughout the South China Sea over the last decade, U.S. weapons development focused on increasing the standoff range, so American forces could stay safe as an outside force shooting in.

But U.S. Marines in the Pacific have continued to operate inside that striking range, and they’re now doubling down with a new concept outlining their role as a stand-in force.

“This is a home game for Marine Forces Pacific. III [Marine Expeditionary Force] lives in the [weapons engagement zone, known as the WEZ] with their families,” Brig. Gen. Joseph Clearfield, the deputy commander of Marine Corps Forces Pacific, said May 11 at the annual Modern Day Marine convention.

Indeed, Pacific Marines are turning conventional wisdom on its head and looking to create their own smaller series of weapons engagement zones inside China’s WEZ — establishing bubbles in and around Pacific islands from which they can dominate in all domains and force China to stay back, rather than ceding the whole South China Sea that’s within striking range of Chinese missiles.

In practice, the Pacific Marines have been the inside force even as the rest of the joint force grapples with the implications of China’s growing anti-access/area-denial capabilities to keep the U.S. and other nations out of the South China Sea and other Pacific waters.

But what was informal is now formal — with the Marine Corps releasing “A Concept for Stand-In Forces” in December to explicitly detail how Marines will live and operate inside the first island chain and, importantly, the additional technological capabilities they’ll need to maximize their contribution to the broader joint force.

“Because the peer threat or the adversary has over the last 20 years really masterfully manipulated the anti-access/area-denial or A2/AD equation to his benefit, it is a difficult nut to crack,” Col. Stephen Fiscus, the assistant chief of staff for force development at Marine Forces Pacific, said during the panel discussion. “For a preponderance of the joint force, based on being outside, they have to work on standoff capabilities to be able to defeat and compete with that weapons engagement zone.”

But the Pacific Marines, and specifically the III MEF forces based in Japan, are now focused on “the ability to stand in, to — by our footprints, our posture, our relationship with partners and allies — to kind of get the enemy in our guard. Instead of standing off at distance, to pull him in using what we have, the relationships we have, our advantages we have, and reverse that equation to create our own WEZ inside of his WEZ,” Fiscus added.

He said the Marines in III MEF are already postured to operate as stand-in forces, based in Japan and training and exercising in places like the Philippines and South Korea. But what the Stand-In Forces concept calls for, he said, is “the ability to gain and maintain custody of targets, maritime targets, and hold those targets at risk with organic or joint force resources to buy space and time for the joint force and enable the maritime fight” — and that will require some new gear.

The eyes and ears for the joint force

Clearfield said he needs more tools that give stand-in forces a “persistent stare” capability, and he needs them as fast as the Marines can field them.

He said he wants to see rapid fielding of tools that will let the Marines attack “persistent surveillance from an adversary and their ability to do over-the-horizon targeting, defeating that, and then responding with like capabilities: our own surveillance, our own reconnaissance, our own intelligence and our own over-the-horizon targeting, precision strike.”

He noted the difference between being able to see the enemy versus having the high-quality data to target them — the data tracking a user’s incoming Uber or Lyft ride, he said, shows the car’s position but not with target-quality fidelity — and said Pacific Marines need more systems that generate target-quality data as well as the ability to pass those targets to weapons in the immediate area or far away.

“I can see the day where the Marine coming out of the [bottom hatch on a helicopter] is going to have a tablet. They’re going to be standing on an archipelago, with a tablet, in a covered and concealed position. They’re going to be masking their signatures so it’s very, very hard, if not impossible, to detect where they are. And on that tablet, they’re going to be grabbing targets and flipping them to firing agencies, some of which may be 1,000 nautical miles away,” Clearfield said.

Col. Tim Brady commands the newly redesignated 3rd Marine Littoral Regiment, which will be one of the key units working as a stand-in force. During the panel, he said one of his top experimentation priorities later this year would be digital interoperability, to understand where there are gaps between where the Marines are today and where Clearfield envisions them in the future.

“How do our systems — across multiple different not only systems but also waveforms — how do they communicate? How do we do that across the joint force — the people, the processes and the systems — to be able to flatten that kill web?” he said, referring to the web of sensors, communication nodes and weapons that must all connect seamlessly.

Even as 3rd Marine Littoral Regiment works through those connectivity issues, the rest of the naval force is coming up with new ways to pursue targets identified by the MLR.

The Navy and Marine Corps continue to test the NMESIS system, or Navy/Marine Corps Expeditionary Ship Interdiction System, a Naval Strike Missile launched off the top of an unmanned Joint Light Tactical Vehicle. Lt. Gen. Karsten Heckl, the deputy commandant for combat development and integration, told lawmakers in a recent hearing that NMESIS, which will be fielded starting next year, went through its most recent round of live-fire testing in April.

Meanwhile, the Navy, using AGM-114L Longbow Hellfire missiles on littoral combat ship Montgomery, “launched sea-based missiles at a land-based target for the first time during a proof of concept exercise, May 12,” according to a news release. The ship fired three missiles at a “land-based target several nautical miles away.”

The demonstration used a MQ-8C Fire Scout unmanned helicopter to provide the ship a target, but that data could come from a Marine littoral regiment in the future.

“Using our speed and shallow draft, we are now uniquely optimized to bring this level of firepower extremely close to shore in support of our warfighters and operators on the beach,” Montgomery commanding officer Cmdr. Dustin Lonero said in the news release.

Lt. Michael Jones, a warfare tactics instructor from the Surface and Mine Warfare Development Center who was involved in the demonstration, called the use of the sea-based missile for land-attack missions part of an “evolving capability to provide enhanced fire support in the littorals and over the horizon in support of the Navy and Marine Corps fighting force.”

“The new ability for LCS to conduct maritime strikes bolsters the ships’ role in conducting shaping operations within amphibious and expeditionary warfare areas,” he added.

Brady said the Marine Corps had to work through the connectivity for this kind of kill web not only with the Navy and the joint force, but also with allies and partners in the region.

“How do we now share that information, that targeting information to be able to flatten that kill web, with our allies and partners? They have weapons systems and capabilities too that they want to employ as part of that stand-in force, right there by our side, that we also need to learn and experiment with.”

Fiscus said early experimentation as part of the Force Design 2030 modernization effort has shown the vision is technologically feasible.

“As a Marine Corps, we’ve answered the question of can we do this as, yes,” he said. “Right now, we can do it in a hermetically sealed room, and it’s replicable. But getting it out in an austere environment where [3rd MLR] are maneuvering in the littorals, alongside a constellation of partners and allies in littoral terrain, to be able to do it sustainably and at scale, I think is what we’re looking for.”

Supplementing the stand-in force

Clearfield said the Marines would be challenged to maintain this persistent stare across the Pacific due to the vast geography. Part of the solution is allies and partners. He said Australia and the Philippines have both established new units that look and operate much like the Marine Littoral Regiment, with a focus on being present to sense and hinder adversary activity on a routine basis.

Another piece, the general said, is refocusing California-based Marines that fall under Marine Corps Forces Pacific.

“The Southern California Marines have been for quite a while manning, training and equipping and preparing Marine formations, [Marine Air-Ground Task Forces], that have spent an awful lot of time in the Middle East doing combat operations,” Clearfield said. “Now that that’s been scaled down, they’re coming back into the Pacific, I would say, in force.”

A Marine Air-Ground Task Force from I Marine Expeditionary Force is now deployed in Darwin, Australia, he said.

With III MEF focused on the first island chain, serving as the inside force closest to China, and I MEF focused on the outer regions of Southeast Asia and able to quickly maneuver in, Clearfield said Marine Forces Pacific is trying to create complementary forces that can conduct traditional amphibious operations and newer operations like expeditionary advanced base operations and littoral operations in a contested environment.

Though Marines out of Japan traditionally covered the Marine Rotational Force-Darwin mission, Clearfield said I MEF out of California will now cover that six-month mission during Northern Australia’s dry season and even potentially spend the other six months of the year pushing a rotational force out into other regional allies and partners.

“There’s a Southeast Asian operational concept for the employment of I MEF in Southeast Asia that is mature conceptually and now being executed, I would say, and it’s just going to get bigger and better as it goes on,” he said.

Megan Eckstein is the naval warfare reporter at Defense News. She has covered military news since 2009, with a focus on U.S. Navy and Marine Corps operations, acquisition programs and budgets. She has reported from four geographic fleets and is happiest when she’s filing stories from a ship. Megan is a University of Maryland alumna.

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