Ronaldus Magnus-Ronald Reagan.
Reason: I'm old enough to remember the economic (and otherwise) mess made by his predecessor...the "Misery Index", Iran, etc... Remarkbly similar to current events, kinda spooky really.
It took Reagan, his vision, his policies, his drive and more than a little help from across the aisle over the course of 8 years to undo the damage Carter did in 4.
It will take a Ronald Reagan-type personality to undo this mess. Problem is, we ain't found one yet.