His graduate supervisor in political philosophy was Professor Sir Isaiah Berlin, OM. He later taught at St Andrews University in Scotland and Yale University (where he has been an Associate Fellow of Davenport College, Yale since 1974). He has lectured at the Kennedy School of Politics in Harvard and also was a Visiting Research Fellow in International Relations in MC, Oxford University. He taught an Oxford seminar in diplomacy jointly with Professor Lord Beloff, FBA, Fellow of All Souls College.
He is the author or co-author of 19 books, including Lord Acton: Historian of Liberty, The Conservative Tradition in European Thought, Forty Centuries of Wage and Price Controls, US Strategy for the Decade Ahead, China: The Turning Point, Korea in the World Today, Saving Social Security, Scholars. Dollars and Public Policy, Toward Liberty, etc.
He also has some administrative experience in government, having served as a senior aide in foreign affairs in the US House of Representatives, as deputy to the Under Secretary of State for Security Assistance, as a senior policy aide in the White House and in the Senior Executive Service in the US Information Agency and the Pentagon (Director of Long-Range Policy Planning). He was also Assistant Director for National Security Policy in a Presidential Transition Office. He was Director of Studies in the largest think-tank in Washington, The Heritage Foundation, and was founding editor of its social science quarterly, Policy Review; he is currently one of its Adjunct Scholars.
He is a member of the Cosmos Club in Washington and of the Beefsteak Club, The Reform Club and of the United Oxford and Cambridge University Club in London. He is also a member of The Pilgrims, the Anglo-American Society.