… is from page 279 of the 1975 collection of some of Harry Johnson‘s essays, On Economics and Society; specifically, it’s from Johnson’s 1973 address “Mercantilism: Past, Present, and Future”:
There is a serious danger to the world economic order of a retreat into mercantilist economic policies as a result of a cumulation of piecemeal decisions the full implications of which, and sometimes even the immediate and obvious implications of which, are never thought through.
Political “pragmatists” often excuse violations of principles – including the principles of free trade – as being necessary to preserve those principles over the long run. Such excuse making in wholly mistaken and almost always a mask either for lazy thinking or, worse, scurrilous motives.