Did Rome correct itself? The enemy is past the gate; in fact, they are us.
Exactly.
Not in Rome, per say, but on a scale of all mankind, yes. In a way, our Republic is in part from the lessons of Rome. Look to the Federalist Papers and see where they studied the past to create our system.
I guess I am optimistic that we will carry forward the lessons of the past. I think that next time (or if we succeed in righting this ship), there will be lessons learned from our history. I believe that our technological advances will allow us to recover quicker.