Final answer:
The role of the military reserves changed before and after the Vietnam War. Before the war, they focused on military security, while after the war, they began to coordinate state policies in various areas.
Step-by-step explanation:
The role of the military reserves has evolved over the years, particularly before and after the Vietnam War. Before the Vietnam War, the military reserves primarily focused on military security, emphasizing the importance of military strength as the most significant component of national security policies. However, after the Vietnam War, the military reserves began to evolve in their function, expanding to coordinate state policies in a wide variety of areas.