Which cause of the Spanish-American War do you think was the most important to the untied states becoming involved

The effort of the United States to rise as a world power.

Explanation:

History has shown that this is what happened. After the American-Spanish War, the United States became a global power. The United States also intended to implement the principles of democracy in its immediate neighborhood, as the press wrote about Spaniards' inhumane treatment by Cubans. These inscriptions served the United States as a means of pursuing its interests.  

b. sec, foreign relations