Since the founding of this journal nearly a century ago, its editors have tried to remain true to the vision of our nation’s founders: to be visionary without seeking utopia, to be progressive without succumbing to doctrine, to be pragmatic without eschewing a passion for ideals. This has often placed us on embattled ground: “to the right of the Left and to the left of the Right”--to borrow an illuminating phrase used by one of the nation’s most imaginative intellectual historians to describe himself.

It is in part for this reason that we pay special homage to that historian, John Patrick Diggins, who died of cancer last week in New York at the age of 73. Although gentle and soft-spoken in his personal demeanor, and refined in his tastes, he boldly embraced intellectual challenge and never shrunk from necessary combat.

As a professor of American intellectual history at the University of California, Irvine, and later at the Graduate Center of the City University of New York, he devoted his restless mind to exploring the origins and the byways of our national experience. In addition to his occasional articles for this journal, and a variety of others ranging from the National Review to the Wall Street Journal, London Review of Books, and University of Chicago Law Review, he was author of twelve books that probed the embattled terrain between American ideals and American ambition.

Whereas other historians often plowed the same familiar fields, Diggins’s restless mind led him into continually new bypasses of the American political experience. It drew him to an inquiry, in his first book, into the response by Americans to Mussolini’s experiment in Italian fascism, and then on to studies of the American left--both New and Old, of the embrace of right-wing conservatism by prominent former leftists, of the influence of the sociologists Max Weber and Thorstein Veblen, of the perennial tension in the American experience between the expansive principles of the Declaration of Independence and the restrictive ones of the Constitution, and to the presidencies of both John Adams and Ronald Reagan.

A contrarian at heart, one as suspicious of the enthusiasms of the left as of the shibboleths of the right, Diggins was inevitably drawn to reexamine the curious presidency of Ronald Reagan. In this complex figure--one as maligned by the left as idolized by the right--Diggins found a true American original, one embodying the values not of Barry Goldwater but of Ralph Waldo Emerson. It was this Reagan who ultimately shook himself loose from Cold War dogma, met Mikhail Gorbachev half way, and together with this dedicated communist ended the Cold War.

It took a historian like Diggins, one brave and self-confident enough to ignore the rules of political correctness, to probe for the truth wherever he might find it--even though this meant pugnaciously declaring Reagan to be “one of the two or three greatest presidents in history”--and offering evidence to demonstrate this provocative assertion.

If John Diggins was an Emersonian at heart, so was he also a man who embodied the fierce passions and warring idealisms of the subject of his final book: Eugene O’Neill’s America: Desire Under Democracy. There he examines the O’Neill who, like Diggins himself, sought to reconcile the great conflicting themes of the American political experience itself: democracy, authority, tradition, and the burden of freedom.

It is appropriate, and our common loss, that at the time of his death, John Diggins had not quite completed his study of the theologian Reinhold Niebuhr, a fellow moralist who probed what he called the “irony of American history.”

Ronald Steel is a professor of international relations and history at the University of Southern California.

By Ronald Steel