Zbigniew Brzezinski, who has died aged 89, was one of the group of European exiles who did so much to steer American foreign policy in the second half of the 20th century. Like Henry Kissinger, Brzezinski was a graduate of the Center for International Affairs at Harvard University. Unlike Kissinger, he was a Democrat, and it was under the Democrat president Jimmy Carter that he served as national security adviser from 1977 to 1981. Those were difficult years: the US was confronted with many traumatic events, among them the world energy crisis caused by the Arab oil embargo; the Iranian revolution and the subsequent capture of the staff of the US embassy in Tehran; and the Soviet invasion of Afghanistan.

Brzezinski also had to deal with the opening of diplomatic relations with communist China and the consequent severing of relations with Taiwan, and with the negotiations that led to the signing of the second strategic arms limitation talks treaty (SALT II). As the Roman Catholic son of an aristocratic Polish diplomat, Brzezinski, or “Zbig” as he was known, had always been strongly a political liberal (in the American sense) in domestic politics, but also a strong anti-communist, and he interpreted these events, more than either Carter or his secretary of state, Cyrus Vance, did, primarily in cold war terms.

Indeed, one of the features of Brzezinski’s years in the White House was the acknowledged rivalry between him and Vance, a liberal Wall Street lawyer, who finally resigned in protest at Carter’s attempt to rescue the Tehran hostages with an ill-fated special forces operation. Before that, the principal cause of discord between national security adviser and secretary of state was Vance’s wish to continue Kissinger’s policy of detente, of which Brzezinski was highly sceptical.

Zbigniew Brzezinski with Henry Kissinger, right, at the Nobel peace prize forum in Oslo, Norway, last year. Photograph: Terje Bendiksby/AFP/Getty Images

Brzezinski was born in Warsaw, the son of Leonia (nee Roman) and Tadeusz Brzeziński. His father was a Polish nobleman and diplomat who served first in Nazi Berlin, then in Soviet Moscow, before being posted to Canada. Brzezinski Jr was meant to study in Britain, but because of immigration restrictions went instead to McGill University in Montreal, and then as a graduate student to Harvard. He arrived there in 1951, just as the study of international relations and regional affairs was being enthusiastically promoted and lavishly funded by foundations connected to the US foreign policy establishment and to the CIA.

The leading intellectual theory at the time was realism, in various competing versions, and doctrines that lent themselves well to the political requirements of the US’s cold war leaders, as well as to the emotional needs of the numerous and intellectually well-equipped émigrés from a Europe that had come to be dominated by Hitler. Unlike academic theorists such as Hans Morgenthau, Robert Strausz-Hupé or JH Herz, or strategic thinkers such as Kissinger and the American-born Herman Kahn, Brzezinski was not Jewish. The emotional theme for him was a Polish suspicion of both Germany and Russia, so anti-communism came naturally to him, more or less uncomfortably married to a liberal idealism.

In 2007, in an amicable joint interview with Kissinger, he professed an idealistic political credo: the next president, he said “should say to the world that the US wants to be part of the solution to its problems and not, in part, the maker of their problems”, and that “the US is prepared really to be engaged in the quest to get people in the world the dignities that they seek today, the social justice that they feel they’re deprived of”.

Earlier, he had subscribed to a more power-oriented view of international relations. He received his PhD from Harvard in 1953 for a thesis on the relations between the Leninism of the October Revolution and Stalin’s state. In 1958 he visited Poland for the first time since his childhood, and his travels in Europe, as well as his later friendship with leading eastern Europeans such as Adam Michnik, reinforced his view that there were profound divisions in Soviet-dominated eastern Europe, a view he developed in his first book, The Soviet Bloc: Unity and Conflict (1967). He taught at Harvard but was not given tenure, and in 1959 moved to Columbia University in New York.

Zbigniew Brzezinski, left, with Jimmy Carter, centre in raincoat, and Cyrus Vance in 1979. Photograph: Bob Daugherty/AP

Politically, Brzezinski was a centrist, or conservative, Democrat. He criticised both the Eisenhower administration’s “rollback” policy towards communism in Europe, and the Nixon-Kissinger detente. He worked for John F Kennedy’s campaign in 1960, and for Lyndon Johnson in 1964, and was in favour of Johnson’s domestic and civil rights policies. However, he was criticised by students and by liberal Democrats for his support for both the Vietnam war, and for the campaign of Johnson’s relatively conservative vice-president, Hubert Humphrey, for president, in 1968.

Brzezinski was active in many establishment foreign policy institutions, such as the Council on Foreign Relations, and the Bilderberg meetings. In 1973, with the backing of David Rockefeller, he helped to found the Trilateral Commission, where he consistently advocated moderation in US policies. All three institutions were the target of paranoid suspicion on the American right. It was through the Trilateral Commission, which advocated co-operation between the US, Europe and Japan, that he met Carter, then known mainly as a liberal governor of Georgia. In 1975 Brzezinski became Carter’s chief foreign policy adviser, and in 1977, when Carter was inaugurated president, his national security adviser.

Probably the most controversial of his policy decisions in the White House was his response to the Soviet invasion of Afghanistan in 1979. The question is clouded by secrecy and contradictory recollections by those involved, but Brzezinski himself recalled that a month or so after the Soviet invasion, he went to Pakistan to co-ordinate the distribution of money to the mujahideen to fight the Red Army. Some have alleged that Brzezinski was in favour of the US financing Osama bin Laden; the truth is that bin Laden’s al-Qaida was only one of many mujahid groups that fought the Soviet invaders and were supported by the US, Saudi Arabia and Pakistan.

It has also been suggested that Brzezinski actually encouraged the Soviet Union to invade because of the damage he saw this would do to Soviet interests in the long run. This last suggestion Brzezinski very plausibly denied. He also denied reports that he encouraged China to support the genocidal dictator Pol Pot in Cambodia, because Pol Pot’s Khmer Rouge were the enemies of communist Vietnam.

After leaving the White House Brzezinski taught first at Columbia and then as director of the Johns Hopkins School of Advanced International Studies in Washington. He continued to interest himself in Russia and eastern Europe, which he preferred to call central Europe after the fall of the Soviet Union, and to write about international affairs.

In 1989 he received a standing ovation from an audience at the Soviet Academy of Sciences when he demanded that Moscow publicly acknowledge Soviet guilt in the murder of 22,000 Polish officers and other members of the Polish elite in the Katyn forest in 1940. He had visited the site of the massacre where he said: “Only with the truth can the new Soviet leadership distance itself from the crimes of Stalin and the NKVD.” Later he told Time magazine that he would not be human if he had not been delighted “when I stood in front of the foreign policy establishment in the Soviet Union”, he said, “and was given a generally empathetic reception, I had a sense of, if you will, historical vindication”.

Perhaps the most important of his later books was The Grand Chessboard (1997), in which he took the ideas of early 20th-century geopoliticians such as Halford Mackinder about the importance of “Eurasia”, and applied them to a world now dominated by a non-Eurasian power, the US. This short, learned, ambitious and even visionary book revealed the mindset of a man who, after almost half a century at the heart of the American foreign policy establishment, remained, in his basic intellectual assumptions, distinct from it.

In particular, he both advised US leaders how they could “perpetuate America’s own dominant position for at least a generation and preferably longer still” and at the same time warned that the US was destined to be not only the first but also the “last truly global superpower”.

Brzezinski is survived by his wife, the sculptor Emilie Benes, and by their two sons, Mark and Ian, and daughter, Mika, and five grandchildren.

• Zbigniew Kazimierz Brzezinski, policy adviser and academic, born 28 March 1928; died 26 May 2017