To a Republican, there are two kinds of American. Real Americans are hard-working, self-reliant, white Christians living in rural areas. The rest of us can be divided into two groups, both of whom live in or around urban areas. One of the groups consists of over-educated, self-satisfied knowledge economy workers who look down on Real Americans; the other includes lazy minorities who do nothing but demand handouts from Real Americans and constantly whine, without any good reason, about bigots and discrimination.
The overriding goal of the GOP is to stick it to the bad guys by denying them public resources. The best way to do this is by cutting taxes and spending. Hence, the orthodox GOP position on spending money on anything other than the military.
The GOP view of urban areas as parasites is, of course, totally at odds with reality; booming urban states are net contributors to left-behind rural areas.. In addition, GOP orthodoxy makes it extremely difficult to help rural residents who have no home in the knowledge-based economy; GOP voters would rather do without the help than do anything that also benefits the bad guys. So what do the red people voting against their economic self-interest get out of the bargain? The satisfaction of remaining rugged individuals, and someone to blame for their troubles. It’s not their fault; it’s the blue people, and the establishment they control, that have caused their misery. Overthrow the corrupt system, and they will prosper again.
The key thing to remember about the Republican creed is that it marries the economic interests of the donor class with the psychic well-being of poor Reactionaries. That is why it persists in spite of the left’s attempts to appeal to workers on pocketbook issues.