The American forces were unable tot win the Vietnam War on the Battlefield. Back in the U.S.A. resistance to the destructive war in Southeast Asia mounted, putting Richard Nixon ever more under heavy pressure tot stop the hostilities. Nixon thought he could win by attacking the Ho Chi Minh trail in Cambodia, expanding the war and challenging China for a response.
Bitter fighting only worsened the situation on the American homefront. Protest were inflamed by the ever rising American casualty count, while the cause of the war didn’t seem justified anymore.