Most comparisons between the United States and the Roman Empire, unless they are extremely specific and bear close mind to the almost incomprehensibly vast difference between the circumstances of Imperial Rome and its inhabitants and the United States, are ahistorical and based on methodology that is generally not acknowledged as accurate by academic historians.

A lot of discussion of Rome's decline in the popular sphere are heavily influenced by Edward Gibbon's The Decline and Fall of the Roman Empire and Whiggish history notions in general. Gibbon argued that Rome fell because a moral decline in the once virtuous populous left them enfeebled and unable to resist barbarian invasions. Gibbon was an Enlightenment historian who approached history in a fundamentally different way than today's historians. He believed in a linear progression of civilizations, a very different notion of virtue than we might hold today, and some very vicious things about Catholics. Many of his arguments regarding the decline of the Roman Empire can be refuted by Roman sources that he simply did not have access to.

As far as comparisons to the United States, by most accounts the U.S. is not a hegemonic empire. Nor is it surrounded on almost all sides by enemies who openly vie for its destruction. Nor is its economy dependent on slavery. We do not have an official religion as the Roman Empire did at the time of its "fall," (though historians generally agree that Rome did not catastrophically fall at any one point. Rather, it declined gradually and it is ambiguous as to when exactly the "Roman Empire" ceased to exist). Fundamentally, none of us inhabits the same mental universe that a person in the late Roman Empire would inhabit, given the nearly two millennia of scientific and intellectual changes between us. So I would argue that, considering all these differences and the many more that I have not listed as I do not have the expertise, comparisons between the two societies must be made very cautiously if they are to be made at all, and that the notion that the United States is "declining like [the Roman Empire] did" is not accurate in any meaningful way.

I hope I haven't made any terrible errors here.

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