Is the Catholic Church Over?

It's not hard to find bad news for the Catholic Church today, whether it be the decline of Christianity in the West, or the increasingly public infighting within the Church (most recently, over Fiducia Supplicans and the idea of blessing same-sex couples), or any number of Catholic Church scandals. Given all of this, is this a sign that the ship is finally going down? Or does some historical context help to make sense of the present messiness? Specifically, what can we learn from the apparent victory of the Arian heresy in the golden age of the Church?

Chapters
0:00 - Intro
0:09 - Overview
4:36 - Dying and Rising Church
10:15 - Death in the Golden Age
12:53 - Imperial Officialism
17:29 - What is Arianism?
20:37 - Constantine, Nicea, and the Nicene Creed
23:18 - Arianism Strikes Back
26:32 - How Bad Did Arianism Get?
39:29 - A Heretical Synod?
52:35 - What Can We Learn from This?