The credibility gap refers to the public's skepticism about the statements and actions of the government, particularly regarding its honesty and transparency during the Vietnam War. This mistrust emerged as discrepancies between official government reports and the reality of the war became apparent, leading to growing doubts about U.S. involvement and the accuracy of information being presented to the American people. The gap between what was said by leaders and what was observed by citizens fueled opposition to the war and had lasting impacts on public perception of the government.