It depends on what you call a “great empire.”
They enslaved a lot of people and used burning Christians for lighting at evening parties.
And obviously, they collapsed.
Radio talk show host Michael Savage, who is religiously Jewish, says that the only hope for America is if there is a resurgence in Protestant Christianity in this country.
Show me an area with religious Christian and I will show you an area that votes Republican and conservative.
By any definition Rome was a great empire. The United States enslaved a lot of people. I still consider it a great nation. The Barbarians did not “collapse” Rome. It decayed from within and the Germanic tribes took advantage of the collapse. At the time of the collapse Christianity was the official religion.