„A doctrine is something that pins you down to a given mode of conduct and dozens of situations which you cannot foresee, which is a great mistake in principle.“

—  George F. Kennan, Context: A doctrine is something that pins you down to a given mode of conduct and dozens of situations which you cannot foresee, which is a great mistake in principle. When the word ‘containment’ was used in my ‘X’ article, it was used with relation to a certain situation then prevailing, and as a response to it. As quoted in "George Kennan Speaks Out About Iraq" at History News Network (26 September 2002)