The idea that people within a state can and should determine the laws within that state is referred to as

The idea that people within a state can and should determine the laws within that state is referred to as  popular sovereignty.

Explanation: Popular sovereignty is an idea that means that the people are the ultimate source of the authority of their government, which means that the people of a state should have the right to determine the laws in their land.

c 3 branches because idk why they had 3 well when:

you think of it there are still contrys with 3

answer; andrew jackson approved nullification by signing it into law,and john calhoun opposed it saying it was unconstitutional;