Some critics have suggested that Ronald Reagan succeeded in a series of careers, ultimately as a two-term president of the United States, by a series of fortunate accidents. Such a criticism is not backed by the evidence. It is true, though, that Reagan's approach to work and life was not conventional.

William McKinley has surely been underrated - in no small part because he was succeeded by a memorable leader, Theodore Roosevelt.

Effective leaders at a high level tend to be skilled actors. Franklin Roosevelt is said to have to quipped, on being introduced to Orson Welles, that they were the two greatest actors in America. The story may be apocryphal, but the message rings true.

Dwight Eisenhower has been underestimated, which may relate to his advanced age in office, his somewhat uneven communications skills, and his failure to present a forward-looking vision on the rising issue of civil rights.

I often ask myself: "What would Theodore Roosevelt do?" One can never know, of course. The ultimate contribution of consequential leaders is often their capacity to reframe issues in novel ways. That said, his leadership engaged, at a foundational level, whether the American "national character" would accept decline and mediocrity, or would go all-in for leadership and excellence. Amid the myriad of otherwise disconnected issues before us, that choice is emerging yet again.

Arguably there's no school for any high position of leadership. That said, Theodore Roosevelt was remarkably well prepared for the presidency. He had held executive positions in the military, in local government, in the federal government.

If leadership is, fundamentally, about serving others, then any one person should be able to move between being a "leader" and a "follower."