Final answer:
The Pentagon Papers, leaked in 1971, exposed significant governmental misinformation during the Vietnam War, revealing secret expansion of the conflict and deliberate deception by the U.S. military and administration. Information included secret bombings, false public statements, and manipulation of wartime success metrics. The Supreme Court ruled in favor of press freedom, allowing the publication of the papers.
Step-by-step explanation:
In June 1971, the publication of the Pentagon Papers had a seismic impact on public perception of the Vietnam War. This classified report, which covered U.S. military actions in Vietnam from 1945 to 1967, was leaked by Daniel Ellsberg, a former military analyst. The Pentagon Papers revealed substantial government misinformation and deceit during the administrations of Presidents Kennedy and Johnson. It brought to light that the U.S. had secretly expanded the war into Cambodia and Laos, helped oust and assassinate South Vietnamese President Ngo Dinh Diem, and that the Johnson administration had planned an escalation of the war while publicly claiming peaceful intentions.
The papers showed a consistent pattern where military and political leaders misrepresented the success and progression of the war to the American public. The leak illustrated that there was a stark contrast between what was being reported by commanders on the ground in Vietnam and the information being presented to the public. Reports of military strategies that were failing and incidents being deliberately misrepresented made the public question the credibility of their leaders and the overall purpose of the war effort. The Supreme Court ruled that the press had the right to publish this information, underlining the importance of freedom of the press and the public's right to know in the face of governmental claims of national security.