What evidence exists to explain early human migration from one region to another?

:) during the cold war, people were afraid of communists, both outside and inside the united states. the red scare and mccarthyism that grew out of these fears were damaging to the american way of life. during the mccarthy years, many of the freedoms guaranteed in the bill of rights were limited. write a paragraph explaining what lessons can be learned from the mccarthy era about what u.s. citizens need to protect in order to preserve the democratic political system and the american way of life.

Can someone me write a paragraph on this topic i feel confused

How might geography have led to greek -city states choosing different gods or goddesses as the protectors of their cities