What is the greatest threat to Army ground formations regarding their ability to communicate beyond line-of-sight?

The greatest threat to Army ground formations concerning their ability to communicate beyond line-of-sight is indeed SATCOM and GPS jamming. In modern military operations, satellite communications (SATCOM) and Global Positioning System (GPS) technologies are crucial for effective command, control, and situational awareness. Jamming these signals can severely disrupt communication and navigation capabilities, rendering the forces less effective on the battlefield, as they rely heavily on these systems for coordination and real-time information sharing.

Effective communication and navigation are essential for maneuvering troops and coordinating operations, especially in complex environments where traditional line-of-sight communication methods may not be viable. When SATCOM and GPS signals are compromised, units may struggle to maintain connectivity with higher command or fellow units, which could lead to significant tactical disadvantages, such as uncoordinated movements or even friendly fire incidents.

In contrast, other threats, such as cyber attacks or artillery fire, while serious in their own right, do not specifically target the fundamental communication infrastructure to the extent of SATCOM and GPS jamming. Physical obstacles, though they may impede travel and line-of-sight communications, do not directly affect the electronic means of communication that are critical in modern warfare.