At the very least, (Thanks be to the Triune God: Father, Son and Holy Spirit!) the dogma of radical inclusivism which taught that God contains all gods and all gods are the same. Such "logic" fails once the devotees of one of these gods refuse to participate and their refusal is legitimized by recognizing, permitting, and endorsing their refusal.
What a judgment on Christendom that Christians were not willing or able to have such fortitude and stand firm for the uniqueness of Him who is the Way, the Truth,and the Life!