as President and declared that the expropiación petrolera did not benefit the economy of Mexico. Cárdenas did not consider this a serious threat and minimized efforts to suppress the rebellion, instead choosing persuasion. The US government did not support the rebellion because it was more concerned that fascist and communist movements from Europe would spread to Mexico. The key to the success of the measures taken by Cárdenas was not just to control the opposition, but to develop and train qualified domestic personnel who could keep afloat an industry that had been maintained thus far by foreign management. The government relied on the Sindicato de Trabajadores Petroleros de la República Mexicana (STPRM, or the Union of Oil Workers of the Mexican Republic) to resolve disagreements over the management of oil resources, and deal with threats of strikes and sabotage. In spite of technical challenges, the local workers who replaced the foreign technicians succeeded in making the new nationalized oil industry work. Josephus Daniels, U.S. ambassador to Mexico, explained to President Franklin D. Roosevelt and Secretary of State Cordell Hull that Cárdenas' reforms could not be undone, since his position as president and the position of PEMEX were secure. PEMEX was and remains a source of collective national pride, and is an international symbol of Mexico. Critics of the expropriation argue that since PEMEX took control of the nation's petroleum, it has suffered from corruption in administrations since that of Cárdenas, and point to its political use by PRI (Partido Revolucionario Institucional) and the PAN (Partido Accion Nacional). In addition, the casus belli of the expropriation was a wage hike of 26 million pesos. In fact, in the short run following nationalization, not only was the promised wage hike postponed indefinitely, wages were actually cut. A tug of war continues between capitalist strategists who favor privatization and popular support for PEMEX as a nationalization success and the backbone of Mexico's economic independence from manipulation by foreign owners and investors. In 2013 a series of privatization measures were undertaken by the President Peña Nieto; in 2019 attempts to walk back such measures and regain Mexican national control over PEMEX were begun by the populist left government of Obrador. See also Nationalization of oil supplies Economic nationalism Petroleum industry in Mexico References Further reading Brown, Jonathan C. Oil and Revolution in Mexico. Berkeley: University of California Press 1993. Brown, Jonathan C. and Alan