Why are republicans Christian, mean and stupid?

Short answer [b]US and Them[/b] . Couple with a[b] black and white world view [/b]L and bonded with [b]faith over evidence[/b] :

[b]Us and Them [/b]
If you had to boil it down to a point of singularity I would offer up that it is self-segregation their creation of the [b]Us and Them paradigm. [/b] I would offer up that in terms of segregation most of Christianity in the USA at least, is like that.

Segregation is a cornerstone of their religion from their self-victimization / their persecution complex to their [i]our values vs your values [/i]in American culture today.

Christian churches both conservative and maybe 1/2 conservative or conversative light (like the Methodists) self segregate most noticeably along racial lines which is the easy way to visibly see their strong desire for self segregation.

You can also see it in their church split offs from the birth of Lutheranism to the recent ideological split of the Episcopalian church over gay marriage.

By other-ing all of us who are not Christians it =makes it easier for many of them to be mean or indifferent to the others. It is also why their is over 300 different kinds of Christianity. Ideological or cultural friction internally creates a new branch. Differences is their Mendoza line.

You probably have friends who are Christians, and some who vote republican (I do) as reader to this in inspire of not being conservative. I can guarantee you have crossed their us-and-them line by being their neighbor, sharing an activity interest with them or something similar.

[b]Black and White [/b]
The second part of it is a black-and-white world view. Seeing with world as good and evil. Most of us non-Christians probably see the world in shades of grey where people are complex and have some good and bad to them. In the construct of Christianity, at least how it is practiced in the USA the adherents tend to categorize many things as evil and good---an over simplification to the complexity that is mankind.

In that idea it is easer for them to take extreme positions on many things the rest of us would be much more apt to see in shades or gray. Many things from them go from good to evil and maybe back almost instantly. in depth thinking isn't really that religions thing. Which gets us to

[b]faith over evidence[/b] Every time you ask them for evidence you either get a personal (and private) revelation or it is just my belief response. Being able to hold a position in absolute certainty based on faith alone is a super-power. It is why they groups don't feel the need to back up their claims on any level and why the rest of us look at them and "[i]wow that is stupid position to hold with no evidence[/i].": You and I and other non-believers are plebeians (others) to them for using evidence to back up our claims on any level. If you look at any particular week in your life you can that condescendence attitude from some Christian you interacted with.

Beyond that you said republican / I would offer up that is all of Christianity in the USA but that republicans have found the nasty-est way to express their us and them, black-and-white- and faith over evidence.