Often, in a given project team or network, one sees leadership roles shifting among various members at various times. Attempts to fit these into traditional views of "leader" and "follower" don't quite work. It's more like Twitter: the "leader" has "followers" - but the "followers" are empowered to alter the relationship unilaterally, and the "leader" must continually earn the consent of the "followers."

My Army reserve service was in the 1990s. It was, more than anything else, an opportunity for me to express gratitude. My understanding of and admiration for the American armed forces is deeper, better informed as a result. I'm among those who believe that military or other citizen service should be an expected part of every American's life.

President-elect John F.Kennedy said to Robert McNamara that there's no school for presidents, or, for that matter, for secretaries of defense.

Everyone knows that Theodore Roosevelt was able to wring so much life out of each day, every hour, every minute. And yet, when one is immersed in a detailed, retrospective review of his life, his intense living, his vigor di vita, is nonetheless breathtaking.

Ronald Reagan was unusual in being an authentic personality. Unlike many professional actors - and politicians - he was much the same behind the curtain as in front.

California is, in many respects, best understood as a nation-state. In the environmental-energy realm, California possesses far-reaching legal authorities that other states do not.

One wonders if Lyndon Johnson and Richard Nixon's administrations may come to be viewed, in the future, as having been underestimated in some respects. To be sure, each ended in failure. Nonetheless, Johnson's accomplishments in civil rights and immigration legislation, and Nixon's in respect to relations with China, may loom larger with the passage of time.