I am not sure what compels the modern Jew to rehearse the downfall of Europe in such a negative cast of light. This is certainly a part of the truth, but it is always presented as "the full orbed Gospel of Yahweh".
One popular comedian argues that it must be dreadful to spend eternity in heaven. No matter how wonderful it might be at first, eventually you're bound to get used to it and end up bored to death. By the same reasoning, one would shrug off the torments of hell over time, and the experience would be the same as heaven. Truth told, Dante's account of the saints contemplating the Godhead in the "Paradiso" section of Dante's Divine Comedy always bored me, without having to wait for too much of eternity to tick by.
Dante was a profoundly mystical writer who was communicating esoteric truth through art.
America's founders also envisioned a new chosen people in a new promised land - Lincoln's "almost-chosen people", and (as Eric Nelson reports in his 2010 book The Hebrew Republic) drew extensively on post-biblical rabbinic sources as well as the Hebrew Scriptures. What distinguishes America from the failed nations of Europe is the absence of ethnicity: because we are founded on a proposition rather than a race, language or common history, America is immune to the tribal idolatry that ruined Europe.
This is so far from the fact that I am astonished that Spengler can keep saying it. America was certainly "propositioned" by somebody, and we by and large have gone for it, and continue to repeat it, hoping that this will save our tawdry love affair.