They say, Babylon is what is bad, a physical place where they do no good, a disease in our minds that prevents us from being honest. Some people say, that the Western civilization is the Babylon. I think Babylon is not one thing, but rather a property. So, a thing can be a Babylon, a manifestation of Babylon, if I think it is.
Who is in Babylon?
Leviathan is one of the rulers. It cannot be defeated by a human.
Moloch is not one person, it is a collective badness of humanity. Moloch is to be slain or saved, the humanity will choose. With kindness, you can both slay and save it.
See /category/babylon for some manifestations of Babylon.