Zbigniew Brzezinski was masterful doer and teacher

Just days ago, Zbigniew Brzezinski, President Jimmy Carter's national security adviser and one of the most brilliant strategic thinkers and practitioners of his time, died at age 89. The distinction between strategic "thinker" and "practitioner" is important. In blunt terms, this difference is expressed in a crisp phrase: "Those who can do -- those who can't teach."

Brzezinski was both a magnificent doer and teacher. His brilliance was equal parts intellect -- thinking that was always disciplined, imaginative and innovative -- and intensity in presenting his case with conviction and certainty. Nor did he lack courage in taking on critics. His stand on Vietnam, the Soviet Union and other issues often led opponents to ostracize him, even for his strong dissent over the 2003 Iraq War that was sadly an accurate precursor of the chaos that followed.

Brzezinski leaves behind an extraordinary family. His wife, Muska, is a highly successful sculptor using huge blocks of wood as her medium. The three children --- Ian, Mark and Mika --- have all pursued highly successful careers in policy, government and the media. However, his passing marks the beginning of the end of a reign of extraordinary national security advisers and strategic thinkers.

Since the end of World War II and the start of the Cold War, three personalities have been the embodiment of what strategic thinking and practicing is all about. Along with Brzezinski, Henry Kissinger and Brent Scowcroft are in this elite group. Brzezinski and Kissinger were foreign born and took their doctorates at Harvard. Scowcroft is a West Point graduate, also a PhD, rising to the rank of Air Force lieutenant general having served as Kissinger's deputy national security adviser under President Richard Nixon and twice as national security adviser, first for President Gerald Ford and then for George H.W. Bush.

While not suggesting an early passing of the remaining members of this extraordinary trio, Scowcroft and Kissinger are in their 90s. However, identifying the qualities that have distinguished these three from contemporaries and successors, many who were inordinately able, suggests why each is and was unique. And it is fair to ponder whether future generations of strategic thinkers and practitioners will rise to that level.

In some ways, the three personalities shared little in common. Brzezinski was always intellectually aggressive. His sharp wit was a penetrating and often humbling form of criticism. His ability to speak directly, crisply, concisely and without ambiguity was legendary. And as Carter remarked, "Zbig always had 10 great ideas a day," a fitting reference to his creative brainpower.

Kissinger tended to be more nuanced and careful in making his disagreements and dissent. Henry was able to deal expertly with Republicans as ideologically diverse as Nelson Rockefeller and Richard Nixon. Like Brzezinski, Kissinger was tough as nails in action.

Kissinger's sense of humor could be marvelously deprecating. When asked why his brother Walter spoke English without an accent, Kissinger responded, "Because he listens."

Scowcroft presented a more modest and less aggressive public image. Trimmer in stature than the other two, he was lower key in making his case. But to confuse that style with any suggestion that Scowcroft lacked the tenacity and intensity to act was a fatal mistake. Indeed, the one shared characteristic among the three was intellectual courage and curiosity, traits seemingly in shorter supply today.

World War II was the crucible in which the intellects and outlooks of all three were forged. All three combined a predilection for academic brilliance with the ability to execute policy. Not all the policies were necessarily well received or yielded long-term political success. Despite the extraordinary Camp David accords achieved under the Carter administration, ably assisted by Brzezinski, that presidency was largely viewed as weak and did not lead to a second term.

The Nixon years were blotted by Vietnam and the interventions into Cambodia and Laos well before Watergate forced a presidential resignation. Kissinger not only survived. He became Secretary of State and his reputation today is that of a global eminence grise.

In many ways, George H.W. Bush's administration was among the most successful regarding foreign policy. While Bush could not be solely credited with ending the Soviet Union, managing the process of "a Europe whole, free and at peace" was masterful. And the conduct of the first Iraq War, expelling Saddam Hussein from Kuwait, was a textbook case for others to follow. But it was the combination of Bush and Scowcroft that led to these successes. For his efforts, Bush was not re-elected president.

Brzezinski's passing marks the beginning of the end of an era of great strategic thinkers and doers. His remarkable career has been well and rightly eulogized by a wide range of admirers from many countries and vocations. His death comes at a time when the United States and the global order are in desperate need of intellects and personalities of his standard. One hopes that one of the many students and staff who studied and benefited from his tutelage will emerge to lead the next generation of great American strategic thinkers and practitioners.

Harlan Ullman has served on the senior advisory group for Supreme Allied Commander Europe (2004-16) and is a senior adviser at Washington, D.C.'s Atlantic Council, chairman of two private companies and principal author of the doctrine of shock and awe. His next book, due out this year, is "Anatomy of Failure: Why America Loses Wars It Starts," which argues that failure to know and to understand the circumstances in which force is used guarantees failure. The writer can be reached on Twitter @harlankullman.