The free world won in 1945 at least in part because the USA, isolated from the conflicts by the oceans, came to its aid.
Who will come to the aid of the USA as it corrodes from within?
The scale of the possible interconnected failures dwarfs that of the fall of Rome. It may rival the simultaneous collapse of the Egyptians, the Hittites, the Canaanites, the Cypriots, the Mycenaeans, the Minoans, the Assyrians and the Babylonians (not to mention the remnant Eblaites, Akkadians, Sumerians, Mitanni, Amorites and Ugarites). Most of those cultures were extirpated entirely in less than a century, to be replaced by Aramaeans, Phoenicians, Thracians, Dorians, Neo-Hittites, Suteans, Chaldeans and eventually Neo-Assyrians.
In the collapse of the 12th century BCE, up to 90% of the towns were abandoned. The entire Mediterranean world was thrown back from Late Bronze Age civilization into the Neolithic. Literacy in several of those cultures was forgotten, leaving ancient writings that can no longer be read. A centuries-long dark age followed.
All the Mediterranean legends of a lost Golden Age, and indeed the cultural belief that each age of the world will be more corrupt than the age before it, may arise from this singular catastrophe. It may have given rise to the legend of Atlantis, as well.
And nobody knows what caused it. Civilization simply fell apart, in many places at once.
And it feels as if we’re playing for similar stakes in our own time.