Short answers, pulled from the story.
James Burnham was an American philosopher and political theorist who lived from the 22nd of November 1905 to the 28th of July 1987. He is best known for The Managerial Revolution (1941), his theory that a new class of managers and technicians was displacing both capitalists and workers, and for his role as a founding intellectual influence on National Review magazine.
Orwell drew on Burnham's Managerial Revolution for the geopolitical structure of Nineteen Eighty-Four, including its three rival superpowers and the idea of a self-perpetuating managerial elite. The character of O'Brien was partly inspired by Burnham's Machiavellian theory of power. Orwell also used the novel as a partial satire of Burnham's admiration for elite governance.
Burnham broke with Trotskyism over the question of whether the Soviet Union was still a workers' state worth defending. The Nazi-Soviet pact of 1939 and Stalin's invasions of Poland, Latvia, Lithuania, Estonia, and Finland convinced him the USSR was a new form of imperialistic class society. He formally resigned from all Marxist organizations by the 21st of May 1940.
The Managerial Revolution, published in 1941, argued that a new class of business executives, technicians, bureaucrats, and soldiers was taking control of modern societies. This managerial class would abolish private property without establishing common ownership, concentrating power entirely in its own hands. The book was included in Life magazine's list of the 100 outstanding books of 1924-1944.
Burnham helped William F. Buckley Jr. found National Review in 1955 and became a lifelong contributor. He wrote a column titled Third World War, treating the Cold War as an ongoing conflict. Buckley described him as "the number one intellectual influence on National Review since the day of its founding."
President Ronald Reagan awarded James Burnham the Presidential Medal of Freedom in 1983. The award recognized his decades of influence on American conservative thought, including his theories of managerial society and his aggressive anti-communist foreign policy positions.