Declinism

Declinism is the belief that other cultures, nations, or institutions are caught up in irretrievable decline.

Typically referred to as a cognitive bias, this belief is easy to come by when looking at the outside evidence and from an ethnocentric point of view and may or may not be a valid conclusion. For instance, when observing another culture and seeing what appears to be a decaying infrastructure and a change in dress and moral strictures one might come to a conclusion that the society that this particular society is in decline, or in a state of "declinism."