… is from page 1 of Volume 2 (“The Law,” “The State,” and Other Political Writings, 2012) of Liberty Fund’s The Collected Works of Frederic Bastiat; specifically, it’s the opening line of Bastiat’s 1834 essay “Reflections on the Petitions from Bordeaux, Le Havre, and Lyons Relating to the Customs Service”):
Free trade will probably suffer the fate of all freedoms; it will be introduced into our legislation only after it has taken hold of our minds.