The greatest presidents have been those who demonstrated astute judgment in times of crisis - often despite the advice they were getting.

The Cold War is over. The kind of authority that the presidents asserted during the Cold War has now been diminished.

Presidents need to be critically studied and analyzed.

As someone who has more than a passing acquaintance with most of the 20th century presidents, I have often thought that their accomplishments have little staying power in shaping popular views of their leadership.

A crisis is an opportunity for a president to step forward and exert effective leadership, and establish his credentials as a significant occupant of the Oval Office.

Despite its flaws, the American electoral system has produced Lincoln, the two Roosevelts, and Harry Truman.