The incident that caused the American antiwar movement to pick up steam in 1970 was the United States of Americas bombing and invasion of Cambodia.
Answer:
The incident made the American anti-war movement gain momentum was the bombing and invasion of Cambodia by the United States.
Explanation:
The impact of the bombing, the subject of much discussion over the last three decades, is now clearer than ever. The killing of civilians in Cambodia has fueled the rise of the anti-war youth movement around the world, highlighting European youth and the great anti-war movement that has moved the United States, as never before.
