Here is a quote from wiki on Post-materialism

First, material needs like hunger or thirst have to be satisfied. If this is done, the focus will be gradually shifting to nonmaterial goods. Hence, according to Inglehart's interpretation of Maslow's hierarchy of human goals, cohorts which often experienced economic scarcities would ceteris paribus place strong priorities on economic needs or economic growth and safety needs as a strong national defense, and "law and order" (materialism). On the other hand, cohorts who have experienced high material affluence start to give high priority to values such as individual improvement, personal freedom, citizen input in government decisions, the...

Here is a quote from wiki on Post-materialism

First, material needs like hunger or thirst have to be satisfied. If this is done, the focus will be gradually shifting to nonmaterial goods. Hence, according to Inglehart's interpretation of Maslow's hierarchy of human goals, cohorts which often experienced economic scarcities would ceteris paribus place strong priorities on economic needs or economic growth and safety needs as a strong national defense, and "law and order" (materialism). On the other hand, cohorts who have experienced high material affluence start to give high priority to values such as individual improvement, personal freedom, citizen input in government decisions, the ideal of a society based on humanism, and maintaining a clean and healthy environment.

Notice how there is a positive feedback between the the recent increasing wealth disparity and the striving for "security" with associated loss of rights. Notice who benefits from that positive feedback and then the policies of the Republican Party make sense. It also speaks ill for the future of the Democrats unless this disparity can be turned around.