Why does a nation of people need its own geographical homeland?
A nation of people needs its own geographical homeland because a nation cannot function and operate unless it is in its own geographical area. The covenant with Abram promised a nation of people, and that promise implied a specific homeland where that nation could exist and operate.
Les explains that in Genesis 12, God made a covenant with Abram, a Syrian from Ur of the Chaldees, not a Jew. God told Abram to leave his country and kindred and go to a land God would show him, promising to make of him a great nation. This Abrahamic covenant promised a nation of people, and Les points out the implication: a nation cannot function and operate unless it is in its own geographical area, its own homeland. So the need for a homeland is inherent in the very concept of nationhood.