On the web everyday are articles by Christians of one persuasion vilifying those of another. It is not just non Mormons against Mormons or Catholics about non Catholics. Everyone knows of these. I’m talking of disputes within narrow bands of Christianity.
Of course, there have always been splits in denominations over one unimportant detail or another. I think the wars are escalating for two reasons. One is politics, the election of Donald Trump. The other is the newly perceived reality that the size of orthodox Christianity, nearly all denominations, is falling. This latter means that to grow denominations, or branches of denominations, need to raid their enemies. For the faith it is a zero sum game. An example of all this can be seen in the commentary after the recent defeat of Roy Moore in Alabama.
Recently a prominent Presbyterian preacher in New York City criticized press coverage of the Moore defeat. He said the press and survey houses asked voters if they were “evangelical”. The preacher went on to say the press should differentiate between those who merely call themselves evangelical from those who are genuine evangelicals. He put the “E” in caps for white Evangelicals who are Moore/Trump political conservatives and called people serious about theology to be small “e” evangelicals. In other words, he or his group should decide who is a legitimate “evangelical”.
By recycling words and religious concepts, each branch of believers can brag only they hold the ultimate truth.