God is responsible for ethnic conflicts
But the LORD came down to see the city and the tower the people were building. The LORD said, “If as one people speaking the same language they have begun to do this, then nothing they plan to do will be impossible for them. Come, let us go down and confuse their language so they will not understand each other.”
So the LORD scattered them from there over all the earth, and they stopped building the city. That is why it was called Babel—because there the LORD confused the language of the whole world. From there the LORD scattered them over the face of the whole earth.
Let's take some tiny leaps of logic: God wanted us not to get along --> Christians believe that everything God does is for the good (the "God works in mysterious ways" thing is just another way of telling you that you're too stupid to understand why bad things need to be done) --> Christians think ethnic conflicts are good --> Christians support ethnic conflicts (they wouldn't want to be against God now would they?).