why did the tet offensive weaken american support for the war
Because the aim of the Tet offensive was to weaken the resolve of the everyday American. It was meant to bring the war home. General Giap was a very strategic man who realised the only way to win against the overwhelming American firepower was to bring the war home. He wanted to the win the war in the court of public opinion. And that was the real aim of the Tet offensive.