Final answer:
Spanish military prowess, marked by superior tactics and technology, played a significant role in their conquests, such as that of the Aztec Empire. However, during internal and colonial conflicts, such as the Peninsular War, the military's limitations became evident, leading to the rise of self-governing juntas in America. The inability to fully control colonies with military force contributed to the decline of Spanish rule in the Americas.
Step-by-step explanation:
The military played a crucial role in the Spanish efforts to gain, consolidate, and maintain power both in Europe and in the Americas. Throughout history, the use of military might was a common practice for empires to assert and expand their influence. In the case of Spain, their military tactics and weaponry were superior to those of the indigenous peoples they encountered, such as the Aztec Empire, which contributed to their success despite being outnumbered.
During the Peninsular War, Spain faced internal strife when Napoléon occupied the country. This event led to the creation of local juntas in its American colonies that began governing independently, which fostered a desire for independence. The Spanish military was also leveraged to suppress uprisings in its colonies, although it was often stretched too thin to effectively quell rebellions, as was the case in Cuba where guerilla tactics by Cuban rebels undermined Spanish control.
In later centuries, Spain expanded its colonial militia and created army units staffed by men born in Spanish America, which was more cost-effective than transporting troops from Spain. Yet, the highest military offices were reserved for Spaniards born on the Iberian Peninsula, known as peninsulares, which caused discontent among the creoles who were born in the colonies. This was one of the factors leading to the eventual weakening of Spain's control over its American empire.