1. How did U.8 involvement in the Vietnam War contribute to the ratification of the Twenty-Sixth Amendment? Congress believed that presidents who served more than two term had too much infuence on foreign affairs African Americans believed that poll taxes prevented them from volcing opposition to wartine policies Congress believed that U.8 intervention in foreign affairs created the need to generate more revenue through income tax reform. Young men believed that they deserved the right to vote if they were expected to serve in the military