People tend to see the world in terms of Us and Them.
I’ve seen Christians foam at the mouth when I tell them, “By all means, don’t believe in evolution…but at least take the trouble to understand what it is you are disagreeing with.”
And I’ve seen atheists foam at the mouth when I tell them, “Look, science is completely incapable of weighing in on any matter of religion, because science ignores religion to keep things simple.”
And we’ve recently seen practically everyone foam at the mouth when the Pope announced that, gee golly, he happens to believe Catholicism is true. (I read one rabbi literally go, in two paragraphs, from “We should be tolerant and respectful of others beliefs” to “The Catholic Church is the path to destruction and death.” )
People have a nasty tendency to parse things into the Good Guys (me and my friends) and the Bad Guys (everyone else).
They care a great deal about truth when it is their friends.
Only with great effort can they find it in them to tell the truth about the Bad Guys if it happens that the truth doesn’t suit them.
It’s easy to say “Evolutionary biologists/ Christians/ Protestants/ Catholics/ Capitalists/ Socialists/ the French are morons.”
It takes some effort to say “Evolutionary biologists/ Christians/ Protestants/ Catholics/etc are smart, sincere people…but history has shown that neither traits protects one from being simply wrong.”