The desintegration of the U. S. Republican Party

What has happened to the U.S. Republican Party that produced people like Abraham Lincoln and Dwight D. Eisenhower? I recognize that educated, well-meaning people are still members of this political organization, but there has been a terrible and clear disintegration in the quality of its candidates. 

Here is a possible explanation: the leaders have developed a double and contradictory loyalty: on one hand they have a natural affinity to big banks and industry because many of their ranks come from these social groups; on the other they realized that they could get support from a large sector of excluded, fundamentalist, and -to a large degree- poorly educated people that dislike liberal values such as racial and ethnic integration. This economically sidelined segment also identifies with wealth: they feel they are one noble step above the “really poor” who deserve to suffer because they are unworthy and lazy. 

These alienated people have another compatibility with big business: they tend to support a foreign policy based on armed intervention and their own “right” to own and use armament; given that the munitions industry is one of the largest in the world, these principles are well-matched with corporate values.

So what happened to the Republicans? They began to incorporate their disenfranchised base to the point of thinking like them. Many of their members distrust formal education (except as a means of climbing the social ladder), and isolate themselves from new and possibly threatening information. 

For these reasons, maybe, they cannot field a decent candidate.