Final answer:
Increasing control over the military in the New World led to centralization in Spain by consolidating political and economic power. However, the exclusion of Creoles from high military roles and the failure to maintain authority during rebellions weakened Spain's control over its colonies, thereby indirectly leading to centralization at home.
Step-by-step explanation:
The increasing control over the military in the New World led to the centralization in Spain due to several interconnected factors. The Spanish Crown's political and economic control over their colonial territories was accomplished by expanding their colonial militia with men born in Spanish America, which also lessened the cost of maintaining the empire. However, they reserved the highest military roles for peninsulares, inducing a feeling of discontent among the Creoles born in the New World.
During the Spanish-American War, Spain's militarized response further weakened their grip on their colonies, particularly in Cuba and Puerto Rico, the last Spanish colonies fighting for independence. Despite attempts to quell rebellions, the colonists grew aware that they were fully capable of self-governance, thus disrupting their obedience to Spain.
Furthermore, Spain's political dominance over the New World had its roots in their ability to effectively tax their populations and recruit soldiers towards their military pursuits. The creation of the intendancy system, although aimed at strengthening Spain's American empire, however, added to creole resentment, furthering the aspiration for independence.
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