Somalia has largely made inroads against al-Shabaab thanks to international assistance. The militant group rose to prominence in the mid-2000s, capturing the capital city of Mogadishu and controlling key ports like Kismayo, in the country’s southern region.

Al-Shabaab was expelled from Mogadishu in 2011 thanks to African Union troops, and then lost Kismayo’s lucrative ports in 2012, putting a dent in the group’s financing. Al-Shabaab continued to lose most of its urban holdings, but remained strong in rural regions.

In 2017, the Trump administration stepped up airstrikes in the country, targeting al-Shabaab leaders and training camps.

But the group remains capable of launching large-scale terror attacks, such as an October 2017 bombing in Mogadishu that killed more than 500 people and a January 2019 attack on a hotel in Nairobi, Kenya.

Some analysts point to these operations, as well as the group’s affiliation with al-Qaida, as evidence of the ability to strike Westerners should it not be checked on the battlefields of Somalia. That is the primary justification for U.S. troops to be fighting, and in one case dying, in the country.

How often do U.S. forces fight?

"Somalia is an area of authorized hostilities,” Marine Maj. Gen. Olson said. "Our intention for U.S. forces is to have the Somali partners conduct the operations. Occasionally, as we’re accompanying Somalis into the field, U.S. forces find themselves in situations where they have to either defend themselves or assist a partner in defending themselves.”

"Those happen occasionally, but the intention of U.S. forces when they take to the field is to advise and accompany the partner where the partner conducts the actions,” Olson added.

The U.S. often operates command and control centers from where they can track partner forces utilizing aircraft sensors and radios, even if Americans aren’t physically involved in the mission.

"We often hear of joint U.S. and Danab missions in different parts of Somalia, and how closely the two forces work together,” said Yusuf, the Kenya-based security analyst. "Literally, Danab cannot operate alone without the needed U.S. support. It heavily depends on U.S. intelligence gathering, and also in supplies and logistics.”

There are various orders that provide U.S. troops the authority to operate in Somalia. Some of those mission names were leaked last year, including several 127 Echo programs, a budgetary authority that allows U.S. troops to control military units from other countries as a sort of "surrogate force.”

While Danab has been an incredibly succesful training program, the regular Somali National Army is riddled with corruption and undermanned. (AFRICOM)

Officials would not comment on which missions are still active and which authorities govern each.

"It’s important to emphasize that the formations that we’re training, advising, assisting either accompany Danab or are part of Danab themselves or are working with [the African Union],” Olson said.

U.S. forces operate across the entirety of Somalia, but there are some places where the effort is more mature, Olson said. There has been a longstanding partnership with the Puntland security forces in northern Somalia, he noted, as well as Baledogle Airfield further south.

"Somalia is the size of the East Coast of the United States. So we have forces distributed from the equivalent of Albany, New York to about Tallahassee, Florida,” Olson said. "And we have a limited number of assets that support them.”

U.S. troops are sometimes outside the wire, as evidenced by the death of Army Staff Sgt. Alexander Conrad, who was killed by al-Shabaab mortar teams in July 2018.

"Every mission that goes outside the wire is supported to a standard that permits us to react to what that force needs, whether it’s fire support, whether it’s personnel recovery, whether it’s medical support,” Olson said. "We carefully examine the minimum force requirements for every single mission, and we help make sure that they’re all supported to the standard.”