What is communalism?

Communalism involves thinking along the following lines. The followers of a particular religion must belong to one community. Their fundamental interests are the same. Any difference that they may have is irrelevant or trivial for community life. It also follows that people who follow different religions cannot belong to the same social community. If the followers of different religion have some commonalities these are superficial and immaterial. Their interests are bound to be different and involve a conflict.