Final answer:
In response to the US invasion of Cambodia, Congress repealed the Gulf of Tonkin Resolution, which had given President Nixon broad powers to wage war without specific congressional approval.
Step-by-step explanation:
In response to the US invasion of Cambodia, Congress reacted by repealing the Gulf of Tonkin Resolution. The invasion of Cambodia angered many in Congress, and their response was to revoke the Tonkin Gulf Resolution, which had given President Nixon broad powers to wage war without a specific congressional declaration. This action demonstrated Congress's disapproval of the invasion and their desire to limit the President's authority in conducting military interventions.