Final answer:
President Taft's address to Congress in 1896 centered on paying off Central American debts to prevent European military intervention and maintaining American hegemony in the Western Hemisphere.
Step-by-step explanation:
The main point President William Howard Taft made in his address to Congress in 1896 was focused on the debt of Central American nations and the potential for European countries to use this debt as a pretext for military intervention in the Western Hemisphere. To prevent such intervention and maintain American dominance, Taft advocated for the United States to pay off these debts, subsequently making the Central American nations indebted to the U.S. This policy led to the imposition of the Lodge Corollary, which stated that no foreign corporations, other than American ones, could obtain strategic lands in the Western Hemisphere, thereby extending the Roosevelt Corollary and actively demonstrating the exercise of American economic and military power in the region.