Examples:

A person who thinks climate change is a real threat to the world is also likely to be pro choice.

A person who thinks gun ownership should be less regulated is also more likely to believe that affirmative action is wrong.

A person who thinks corporate taxes should be lower is more likely to believe that dinosaurs are a hoax than someone who wants to raise corporate taxes.

An assumption I'm making about the above examples is that they really are totally unrelated issues. In reality, maybe they're related in ways I'm not understanding, or maybe there is (to some extent) a "politically left" personality type and a "politically right" personality type. Even if either of these things is somewhat true, I think it's hard to debate that history can explain at least in part the fact that seemingly unrelated views are held together consistently by people of any political party. Overall, this is a very complex question that probably has a multitude of correct answers. I hope to get thoughts from many different perspectives!

Also, I understand Christianity was a huge factor in the American Right's stance on social issues, so I guess my question is really "how did those social mores get tied up in denying climate change and lowering taxes for the rich?"

Political historians: if your answer is "Reagan's unified the fiscal and social conservatives" please tell me HOW! Also, can you really attribute the differences in the views of the constituents of the two major political parties in the late 20th century to one guy who certainly seemed like he hadn't given the steering of the ship all that much thought? If not, whose idea was it to unite the fiscal and social thinkers under the Republican party? I doubt it was Ronald's...

P.S. Sorry my bias is showing in this post!