George Kennan, the American diplomat and Pulitzer Prize winner, who was a leading architect of the US' Cold War policy, has died aged 101.
Kennan was a leading strategist of the Cold War
In a now famous article in 1947 signed "X", he formulated the "containment" policy to curb Soviet expansionism.
He advocated the use of diplomacy and politics to counter the spread of Communism rather than military action.
US historian Ronald Steel said he was the "nearest thing to a legend" the US diplomatic service has ever produced.
Cold war historian John Gaddis, who is writing a biography of Mr Kennan said: "He'll be remembered as a diplomatist and a grand strategist."
He died in his home in Princeton, New Jersey, on Thursday night. He is survived by his wife, Annelise, three daughters and a son.
His ideas on Soviet containment were first expressed in what is considered to be the most famous cable in US diplomatic history, his 5,542-word "Long Telegram" from his posting at the US Embassy in Moscow in 1946.
It explained to US policy-makers that while Soviet power was "impervious to the logic of reason," it was "highly sensitive to the logic of force."
The telegram made Mr Kennan famous in Washington and his ideas were disseminated through a highly-influential article written under the pseudonym "X" published in 1947.
"It is clear that the main element of any United States policy toward the Soviet Union must be that of a long-term, patient but firm and vigilant containment of Russian expansive tendencies," he wrote.
But when the containment policy was used to justify military ventures such as the Vietnam War, Mr Kennan, who objected to the emphasis on military containment, said his original proposal had been misinterpreted.
He became an fervent advocate for disarmament, believing that the arms race between the Soviets and the US was the biggest threat to both nations.
Persona non grata
Born in 1904 in Milwaukee, Mr Kennan entered the foreign service a year after graduating from Princeton University in 1925.
He served several postings in Europe, including Berlin, Vienna, Prague and Moscow, and took a lead in devising the Marshall Plan, which sent billions of dollars of aid to European countries devastated by World War II.
Appointed ambassador to Moscow in 1952, his mission ended abruptly after five months when he was declared "persona non grata" by the Soviets for comparing life in the US Embassy to a Nazi internment camp.
After his last post as ambassador to Yugoslavia during the Kennedy presidency, Mr Kennan continued to be an influential thinker on foreign policy, based at the Institute for Advanced Study in Princeton.
He wrote 17 books and two of them, Russia Leaves the War (published in 1957) and Memoirs: 1925-1950 (1967), won Pulitzer Prizes.