Dolores Huerta's leadership in the national boycott of lettuce was important because she mobilized workers and consumers across the country to protest the poor working conditions and low wages of farmworkers. This boycott drew attention to the mistreatment of farmworkers and led to the formation of the United Farm Workers union, which advocated for better working conditions and higher wages. The boycott also brought national attention to the struggles of marginalized communities, and helped to inspire other social justice movements.