Damn, I hate parallels like this one.
The fall of Rome was a pretty complex process. As such, you can easily find things to point to if you want to draw a parallel between it and any major power in trouble. However, it's just as easy to point to major factors with no clear analogies.
Moreover, the phrase "declining moral values and political civility at home, an over-confident and over-extended military in foreign lands and fiscal irresponsibility by the central government" is just plain wrong on a number of counts.
(1) If by "moral values" you're referring to the usual thing (i.e., sexual mores and hedonism), the late Roman empire actually saw a *tightening* of such values, as Christianity became the state religion. The high point of the Roman empire -- the period of the "Five Good Emperors" from Nerva to Marcus Aurelius -- was actually characterized by very permissive mores. Of course, if you're referring to stuff like corruption, nepotism, profiteering, and what have you, you could paint a different picture.
(2) The military during the late Roman empire was not, in fact, "over-confident and in foreign lands." If only. It was within the empire, keeping down insurrections at home and barbarians at the borders -- but it was no longer loyal to the central authority in Rome, rather than individual generals. That meant that whoever had the most loyal legions got to be Emperor, and the Praetorian Guard got to decide how long they stayed that way.
I'll give you fiscal irresponsibility -- that happened for sure. The Roman Empire was running huge deficits for a long time, pissing away the treasury to buy luxuries from the East. There you could draw a better parallel with the US, since the fiscal irresponsibility was largely caused by a huge disparities in wealth -- the poor were miserable to start with and only got poorer and more numerous, while the rich had all the power and just kept getting richer, which isn't that different to developments in the US lately.
However, the main problem with the parallel is that it misses both the major ultimate cause for the decline, as well as the obvious proximate cause. Namely, the decline of productivity due to ecological damage, and the little matter of the Huns -- or, actually, the huge population movements originating in Central Asia. Eastern Rome survived for another thousand years because they weren't hit as hard by the barbarian hordes, y'know.
Finally, the USA isn't Rome. The polities have hugely different social and political structures, values, capabilities, and histories. For starters, Rome's ascendancy lasted a half a millennium, while America's only been a great power less than a century, and a hegemonic one for little more than 50 years.
So the parallel isn't really very useful, other than as a rhetorical device.