Looking back as an historian, I find myself having great respect for Ronald Reagan's consistency: his absolute conviction that the Soviet Union - the only competing world empire at the time - was bound to collapse!
Dwight D. Eisenhower, in my judgment, will go down in history as one of the four 'great' presidents since the U.S. reluctantly became an empire in World War II; Richard Nixon as the nearest to a sociopath by the time he was compelled to resign.