Ground-based drones are already in development that are intended to serve as support vehicles for ground troops in combat zones. The drones can carry equipment and even (in some cases) operate weaponry.
For years, long-range, high endurance airborne drones have been used as both surveillance vehicles and offensive weapons, providing intelligence and destroying enemy targets without endangering human pilots.
Small, insect-based aerial drones can monitor hostile environments in a greater range of weather conditions (and on less power) than their larger counterparts.