Operational planners did factor res

Operational planners did factor resistance groups in as a means to frustrate German reinforcement plans. The challenge they were forced to balance was in prioritizing resources needed to support the main thrust of the Allied fight and resources needed to support an unknowable program of underground resistance. They thought that reinforcements by road would be negligibly impacted, but reinforcements by rail could be impacted by days.39 Delays in terms of days were a factor that would make a difference in Allied efforts to expand the lodgment rapidly. The interference of rail systems, therefore, was a prime objective for both air operations and resistance groups. By air, the Allied command could destroy broad sections of rail. By ground, they could rely on resistance groups, directed by special operations teams, to inflict damage with more precision. The combination of broad air effects and precise indigenous effects, according to the plan, could create depth to the degree of rail destruction.40 Nevertheless, despite the relative newness of special operations as an organizational component of large-scale operations, SHAEF planners did incorporate special operations activities into the plan. Additionally, field commanders, such as the 12th Army Group, First Army, and Third Army used their liaison relationships with Special Force Headquarters to take advantage of operations done with and through French resistance.