In addition, U.S. military personnel throughout Syria have increasingly had to contend with other factions, including Kremlin-linked mercenaries , militias aligned with the country’s dictator Bashar Al Assad, and Iranian-backed groups . American troops have actually come to blows with all of these groups, as well as Turkish-backed Free Syrian Army fighters .

American special operators have been working closely with those fighters in that particular part of Syria since at least March 2017 when they first appeared in order to effectively block Turkish-supported factions from moving into the area. The United States and Turkey, as well as their respective partners, are increasingly in an armed stand-off in the country over America’s support for the SDF, which Turkish authorities say is a terrorist group in its own right. You can read more about that complicated dispute here .

Earlier in April 2018, Kurdish media reported that U.S.-backed Syrian Democratic Forces, a group also known as the SDF that predominantly consists of Kurds, had established two new operating sites near the strategic city of Manbij in northern Syria. Subsequent images and video showed that American special operations forces were also present and had brought mine-resistant trucks , Humvees , and other vehicles with them , as well as heavy weapons, including .50 caliber machine guns, automatic 40mm grenade launchers, and the AMPS .

As the conflict in Syria continues to evolve , the U.S. government is re-examining what its future presence in the country might look like and for how long. In the meantime, American troops there are settling into increasingly more established forward outposts with improved defenses, including the futuristic-looking Advanced Mortar Protection System, or AMPS.

“We’re going to continue to improve our defenses, that’s what’s going on around us to this day and rehearse our plan and hope it doesn’t happen again,” U.S. Army Brigadier General Jonathan Braga, director of operations for the main U.S. military task force in charge of operations in Iraq and Syria, told NBC's Richard Engel in March 2018. The officer was referring specifically to the situation in the country’s Deir ez-Zor governorate, further southeast of Manbij, but the attitude seems to apply to American operations elsewhere. And that’s where the AMPS would seem to come in. At its core, the system, also known as the XM905, is a relatively portable 120mm mortar on a rotating base plate so troops can fire it in any direction. Defense contractor Mistral, Inc., in cooperation with Israeli firm Elbit, produce the weapon.

Mistral, Inc. The XM905 Advanced Mortar Protection System, also known as the Improved Enhanced Mortar Targeting System (EMTAS).

Unlike many traditional infantry mortars, the weapon itself, called the XM908, has a recoil mechanism, giving it the appearance of a small howitzer, which helps reduce the shock of firing and improves accuracy. Three feet attached to the weapon's base plate further stabilize the firing platform. The mortar, a derivative of Elbit’s Cardom Recoil Mortar System 6-Light, or RMS6-L, is the same one the U.S. Army employs on some of its Stryker wheeled armored vehicles. The weapon's base has its own battery-powered traverse system that can slew the weapon 180 degrees in 12 seconds to fire automatically at coordinates troops input into a computerized fire control system. The motorized arrangement can still aim the weapon accurately even if the platform isn’t on level ground.

US Army Troops in an M1129 Stryker Mortar Carrier Vehicle fire their 120mm mortar, which is the same as the one found on the XM905 AMPS.

The mortar has a maximum range of between four and five miles, depending on the ammunition type, which can include high explosive rounds, shells that create concealing smoke, and ones that release illuminating flares for night-time operations. Combined with the computerized fire control system, the earliest versions of the system could reportedly hit targets within an area approximately half a percent as wide as the firing distance. This means that at a mile, the crew can expect the shell to fall within a circle less than 30 feet wide. Closer in, it can deliver more impressive results and rapidly. But more importantly, it offers immediate extended range fire support for troops at remote bases, who may not have the time to wait for other artillery or air support to become available. And that has been the goal of the system since it first entered service in an almost emergency capacity in 2011. The year before, the Pentagon’s Combating Terrorism Technical Support Office, or CTTSO, rushed 10 of an earlier version of the system, then known as the Enhanced Mortar Targeting System, or EMTAS, to special operators and conventional Army and Marine units in Afghanistan. That entire effort cost nearly $9 million. “Existing Forward Operating Base (FOB) defense systems currently provide only the capability to detect, provide warning, and assess potential threats,” a subsequent Pentagon budget document explained in requesting additional funds to sustain the project. “At smaller, more remote locations, the kinetic response capability is limited only to existing organic weapon systems, which can become overwhelmed; or, to supporting arms which may be unavailable due to weather, competing requirements or Rules of Engagement (ROE).”

CTTSO An overview of the CTTSO's original EMTAS project.

In 2013, another urgent request from special operators in Afghanistan called for more and better versions of the system to guard their operating sites, resulting in the Improved EMTAS. The Pentagon’s Rapid Reaction Technology Office, or RRTO, coordinated that program, which the Army subsequently managed. The service then rebranded the weapon as the AMPS and continues to support the system on behalf of the special operations community. Elbit also offers a further improved version of the system, known as the Spear Mk 2, for a wide variety of vehicle and dismounted applications. In Syria, where battle lines and the allegiances of certain groups can change rapidly, having the mortars in place gives American troops and their partners significant firepower in the event that they come under attack. It’s no surprise that the forces in Manbij, who are now concerned about a new Turkish-backed intervention, have decided to move the weapons into place to help guard their positions.

Joseph Trevithick Elbit's Spear Mk 2 on a Plasan Sandcat 4x4 light vehicle.

“I want to get out – I want to bring our troops back home,” U.S. President Donald Trump said at a press conference on March 3, 2018. “It’s time. We were very successful against ISIS.” But the presence of these heavily fortified sites, defended in part by emplaced weapons such as the computer-assisted mortars, seems to suggest that American troops are expecting to remain in Syria for the foreseeable future. Correction: The original version of this article said that the initial versions of the EMTAS had the ability to hit within an area with a diameter equivalent to five percent of the range. The stated accuracy was in fact half a percent. Contact the author: jtrevithickpr@gmail.com