The US Army is back in the jungle. Panamanians are showing soldiers the way.

Gunshots erupted from solid ground towards a boat that ferried Panamanian soldier Albis Fajardo and his team during a counter-drug mission along the country’s Pacific coastline. The team attempted to return fire as they pulled back from a harrowing effort to target a cartel leader. Fajardo, then early into his military career, felt his adrenaline surge as he realized the team had been unsuccessful: A bullet had torn through the flesh of his friend. Over a decade later, with the early autumn sun sinking over Panamanian base Aeronaval Cristóbal Colón, the 47-year-old, now a first sergeant,…