The Vietnam War Practice Test

A historian writes: “By 1965, U.S. leaders treated Vietnam as a test of credibility. After incremental aid and advisors failed to stabilize South Vietnam, Washington expanded the war through sustained bombing and large-scale ground deployments, expecting superior firepower to force a political settlement. Yet escalation often strengthened enemy resolve and deepened U.S. dependence on an unstable Saigon government.” Which development most directly marked the shift to major U.S. ground combat operations described here?

A historian writing about antiwar opposition argues that televised images of combat and rising U.S. casualties interacted with a draft system that many Americans viewed as inequitable, fueling student activism and broader protest. The historian cites a 1969 event in which millions participated in coordinated demonstrations and vigils nationwide. Which protest event best fits this description?