"Free enterprise has destroyed itself," Pope Pius XI said in 1931, and has been replaced by an "international imperialism whose country is where profit is." No wild-eyed radical or flaming liberal, Plus XI was one more in a long line of conservative Roman churchmen raised to the papal office. His elaborations about the world's economic systems, delivered in his encyclical Quadragesimo Anno, have particular relevance this year, since the whole network of international trade and finance has come under severe attack by the actions of President Nixon in August, and the subsequent reactions of other nations.