American exceptionalism is based on four pillars that NO other nation had at the time of its founding (some developed some later, but almost none have all four):
1) A Christian, mostly Protestant religious foundation. (This eliminates all nations right off the bat except England, Canada, and Australia, and England was mostly "Anglican," which traditionally isn't viewed as "Protestant," while Canada had a heavy dose of Catholicism from the beginning.)
2) A heritage of common law, as understood as a system of laws in which God puts the law in the hearts of the people and they elect rulers to enforce what they already know to be right and wrong. Again, with the exceptions above---and England is rapidly losing this with Sharia Law on the one hand and infringements of French Civil Law via the EU on the other---no one else in the world has this.
3) A free market.
4) Private property rights with written titles and deeds.
Again, we are the FIRST nation in the world to have these pillars, and with the exception of Australia---which is not heavily Protestant---the only nation to possess all four from its outset.
The cancer we allowed to go untreated has became malignant and metastasized .