GEORGE C. MARSHALL Statesman, 1945-1950 By Forrest C. Pogue Viking. 603 pp. $29.95

FORTY YEARS AGO this month, it has been widely noted, Secretary of State George C. Marshall unveiled to a commencement gathering of Harvard alumni a plan pledging massive economic development funds to strengthen Western Europe against communism. In fact, as Forrest C. Pogue makes clear in this fourth and final volume of his definitive biography of Marshall, the secretary s brief speech set forth not a plan but an offer, extended not to Western Europe but to all of Europe, focusing not on economic development or communism but on postwar recovery and reconstruction, pledging not specific sums but a national commitment, and reflecting not Marshall s thinking alone but also that of George Kennan, Dean Acheson, William Clayton, Charles Bohlen, Walter Lippmann and a host of others.

Not the least of these was President Harry Truman, who had the good sense to start calling this program the Marshall Plan when he sought its enactment and funding by the Republican-controlled 80th Congress in a presidential-election year. Primarily for this unprecedented act of national generosity that thus bore his name, Marshall won the Nobel Peace Prize. But Truman won the election.

Writing an authorized and admiring biography of a genuine American hero, in which every Marshall critic is rebutted and no major flaw detected, Pogue, still the careful historian, makes no claim that Marshall invented the European Recovery Program (as the Marshall Plan was officially known). Nor does he claim that Marshall, an instinctively cautious man slow to commit himself and his country, was a great innovator in one of the most innovative periods in American foreign policy. The Truman Doctrine, NATO, the Berlin Airlift, the InterAmerican Pact, the recognition of Israel and other U.S. initiatives during Marshall s tenure at State were primarily the initiatives of others in the department, White House or alliance, some of them launched with a speed or speech not to the secretary s liking.

Yet his judgment and leadership were crucial. Accustomed to a chain of command -- he had served as chief of staff of the army during World War II -- Marshall made no pretense of administering the Department of State, leaving that task to his undersecretary -- first Dean Acheson, then Robert Lovett -- and establishing the Policy Planning Staff for long-range thinking. Although a blunt, plain-spoken man, he ably articulated his department s and president s policies before Congress and in public speeches. Presiding over a brilliant collection of diplomats, Marshall was, writes Pogue -- who has crosschecked the memos and memoirs of all concerned -- a quiet and patient listener and decision-maker more interested in results than problems.

THIS VOLUMINOUS work, concluding 30 years of exhaustive research and writing, occasionally bogs down in detailed accounts that may blur the larger picture to a generation unfamiliar with the postwar era. For example, a week-by-week narrative of Marshall s first post-military assignment, hopelessly trying to end civil war in China, is given half again as much space as his more fruitful though briefer service as secretary of defense. But any portrait of Marshall requires contrasting hues:

Foreswearing presidential ambition when named secretary of state, his standing with both parties was so high that Senate Foreign Relations Chairman Arthur Vandenberg rushed that nomination through his Republican-controlled committee and Senate without one day s delay or one negative vote. But only a few years later the Republican right, led by senators Joe McCarthy and William Jenner, savagely questioned Marshall s competence, honesty and loyalty in Senate floor speeches replete with malicious innuendo. The most popular Republican of the time, Marshall's former prote'ge', Dwight Eisenhower, failed to defend him.

Marshall owed his appointments as secretary of state and secretary of defense (as well as the prestigious but more relaxing post of American Red Cross chairman in between) to his warmest admirer, President Truman. But, convinced that Truman s position on the creation of Israel was taken in election-year haste spurred by White House Special Counsel Clark Clifford (whose relations with the secretary of state were not unlike those of subsequent national security advisers, a post not then established), Marshall sternly told the president that, on that basis alone, he would vote against him "if in this election I was to vote." (Carrying a military non-partisanship to an extreme, Marshall had never voted.) Truman also had to be dissuaded at the last moment by Lovett from sending Chief Justice Fred Vinson on a special election year mission to Moscow that would have publicly undercut Marshall s long, painfully frustrating dealings with Stalin and Molotov.

As secretary of state and later secretary of defense, Marshall was so committed to a policy of firmness backed by a full-strength unified U.S. military (including nuclear weapons, then an American monopoly) that revisionist historians have cited him among those responsible for initiating the Cold War. But long years in the service fortified Marshall s publicly expressed conviction that Chiang Kai-shek could not defeat the armies of Mao Zedong, that Douglas MacArthur s headstrong tactics in Korea were risking a world war in defiance of civilian authority, and that U.S. security interests would not be served by a policy of confronting communism with force everywhere and anywhere in the world. Indeed, we would do well today to adopt his words at Harvard 40 years ago:

"Our policy is directed not against any country or doctrine, but against hunger, poverty, despotism and chaos . . . to permit the emergence of political and social conditions in which free institutions can exist."

William F. Buckley Jr. and L. Brent Bozell claimed that McCarthy, in his vituperative and unfounded attacks on Marshall, "performed a valuable service" because they "contributed to cutting Marshall down to size." Hardly. But Forrest Pogue, at a time when a few retired generals and others have sullied the public honor of the military by pursuing their private interests, has indeed performed a valuable service in faithfully portraying the outsized talent and dedication of one old soldier who never faded away. :: Theodore C. Sorensen, former special counsel to President John F. Kennedy, now practices international law in New York.