- Poor military strategy: Spain made several strategic mistakes, such as concentrating their fleet in Manila Bay, which allowed the Americans to easily destroy it. They also relied heavily on outdated ships and tactics, while the Americans had a more modern navy and used innovative strategies such as the "blockade and destroy" tactic.
- Inadequate naval power: Spain had a smaller and weaker navy compared to the United States. This made it difficult for them to defend their colonies and engage in naval battles effectively. The American navy, on the other hand, was stronger and more technologically advanced.
- Lack of support from colonies: Many of Spain's colonies were already suffering from internal unrest and discontent, and they did not provide strong support to Spain during the war. In some cases, such as Cuba, the locals actively supported the American forces.
- Financial difficulties: Spain was experiencing severe economic problems, which limited its ability to finance the war effort. The United States, on the other hand, had a stronger economy and was able to provide more resources for the war.
- Yellow Fever Outbreak: The spread of Yellow Fever severely reduced the number of effective troops Spain had available in Cuba. At one point, over half of the troops in Cuba were infected.
- American public support: The Spanish-American War was widely supported by the American public, who were eager to expand the country's influence and gain new territories. This gave the American government more political and moral leverage in the conflict.
- International diplomacy: The United States was able to secure support from other countries, including Britain and Germany, which put pressure on Spain to negotiate peace.
In conclusion, the Spanish-American War was a decisive victory for the United States and marked the decline of Spain's global power. Spain lost several colonies as a result of the war, including Cuba, Puerto Rico, Guam, and the Philippines, and its influence in the world diminished significantly.