During the next four decades, Mexico experienced impressive economic growth, an achievement historians call "El Milagro Mexicano", the Mexican Miracle. A key component of this phenomenon was the achievement of political stability, which since the founding of the dominant party, has insured stable presidential succession and control of potentially dissident labor and peasant sections through participation in the party structure. In 1938, Lázaro Cárdenas used Article 27 of the Constitution of 1917, which gave subsoil rights to the Mexican government, to expropriate foreign oil companies. It was a popular move, but it did not generate further major expropriations. With Cárdenas's hand-picked successor, Manuel Avila Camacho, Mexico moved closer to the U.S., as an ally in World War II. This alliance brought significant economic gains to Mexico. By supplying raw and finished war materials to the Allies, Mexico built up significant assets that in the post-war period could be translated into sustained growth and industrialization. After 1946, the government took a rightward turn under President Miguel Alemán, who repudiated policies of previous presidents. Mexico pursued industrial development, through import substitution industrialization and tariffs against foreign imports. Mexican industrialists, including a group in Monterrey, Nuevo León as well as wealthy businessmen in Mexico City joined Alemán's coalition. Alemán tamed the labor movement in favor of policies supporting industrialists.

Financing industrialization came from private entrepreneurs, such as the Monterrey group, but the government funded a significant amount through its development bank, Nacional Financiera. Foreign capital through direct investment was another source of funding for industrialization, much of it from the United States. Government policies transferred economic benefits from the countryside to the city by keeping agricultural prices artificially low, which made food cheap for city-dwelling industrial workers and other urban consumers. Commercial agriculture expanded with the growth of exports to the U.S. of high value fruits and vegetables, with rural credit going to large producers, not peasant agriculture.