Yep. Bears repeating in words, 'cause empires have done it often enough.
I have always found that Khaldun expresses the rise and fall of a people best:
“A victorious people settles down after victory to enjoy its new conquest, whether new lands they have expanded into, or a new regime that has taken over the existing land.
“They grow in complexity of social relations and authority is concentrated and institutionalized to maintain order.
“With order comes growth in wealth and education. Science, philosophy and arts grow. Cities grow as rural life diminishes. Urbanization and widespread comfort mark the beginnings of decay.
“The enriched society comes to love pleasure, luxury, and ease, over work, risk, and martial strength. Religion weakens, morals become confused and deteriorates, pederasty and homosexualaity and other abnormal practices grow. Foreigners are brought in and used for the work. These lack natural patriotism to assist and defend the ideals of the society that are now nebulous and weakened.
“The troubled society invites conquest, whether from without, or by revolution or intrigue from within. The cycle begins again at phase one.”
Tell me that’s not us.