How did the government fight terrorism on the home front?

The case was finally broken open in the summer of 2002. Confronted with evidence obtained through electronic surveillance and other means, the six admitted that they had gone to Afghanistan the previous year and pleaded guilty to training with a terrorist organization. The successful investigation demonstrated the value of sharing government intelligence with law enforcement officials. But even that information could not reveal why the six had gone halfway around the world.

They needed to add new constitutional amendments after the civil war because the civil war was about freedom for black Americans which meant that the amendments were intended to guarantee the freedom of former slaves and to establish and prevent discrimination in certain civil rights to former slaves and all citizens of the United States.