Eastern Orthodox Excommunication Dilemma

[DeFide]

From “Why I Am Not Eastern Orthodox”:

As I learned more about Orthodoxy, another set of factors seemed to weigh against it.

Both Eastern Orthodox and Catholics say the Nicene Creed’s affirmation that the Church of Christ is “one, holy, catholic, and apostolic,” but which has the better claim to those notes? …]

…[T]he Orthodox communion has an issue when it comes to being “one.” I’m not referring to the dissent and division that has been part of every Christian community since the beginning. I’m referring to the fact that not all Orthodox churches are in full communion with each other. There are situations in which church A is in communion with church B, and church B is in communion with church C, but A is not in communion with C. For example, the Russian Orthodox Church Outside of Russia is in communion with some Orthodox churches but not others (notably the Russian Orthodox church).

The reason the Orthodox justify their view of still being Christ’s one true Church despite the schism is that that they view their various church structures as being equal, with the successor of Peter merely being a “first among equals” at best, and so therefore no one has supreme authority in the Church, as Catholics claim.

But the very act of excommunication blows that claim out of the water. Excommunication, by its very nature, flows from a position of supreme singular authority. Equal United States Supreme Court justices cannot boot each other off the bench, as an analogy.

Let’s say in the future there are only two Orthodox Churches, named “A” & “B”, both “equal”, and the Catholic Church, which the Orthodox twins still agree to reject.

Now if Patriarch “A” excommunicates Patriarch “B” and all who dare follow him, and Patriarch “B” reciprocates in the same dispute (as would naturally occur), who is right? Did the gates of Hell prevail against Christ’s Church? Aren’t they both acting as supreme authorities and admitting by their actions the Catholic Church was right all along?