The United States declared war on Spain in 1898 for a variety of reasons, including domestic political pressure, ideological differences, and overseas expansion.
One of the main drivers of the Spanish-American War was domestic politics. At the time, the United States was in the midst of the Gilded Age, a period of rapid economic growth and political corruption. Many Americans were advocating for overseas expansion as a way to extend American influence and promote economic growth. Additionally, there was a strong sentiment among some Americans that the United States had a moral obligation to spread its democratic values to other countries.
Another factor that contributed to the declaration of war was the ideological differences between the United States and Spain. Spain was a colonial power with a long history of controlling territories in the Caribbean and Central and South America. The United States, on the other hand, saw itself as a defender of democracy and freedom. This difference in ideology led to tension between the two countries, particularly in the Caribbean, where Spain had a number of territories.
Finally, the United States also had a desire for overseas expansion. At the time, many Americans saw the acquisition of overseas territories as a way to increase the country's power and prestige on the world stage. The United States had already acquired a number of territories, including Puerto Rico and Guam, and the Spanish-American War provided an opportunity for the United States to expand its influence even further.
In summary, the United States declared war on Spain in 1898 for a combination of domestic political pressure, ideological differences, and a desire for overseas expansion. The war had significant consequences, including the acquisition of new territories and the emergence of the United States as a global power.