Article 27 of the Constitution empowered the state to expropriate private holdings if deemed in the national interest and returned subsoil rights to the state. It enshrined the right of the state could expropriate land and redistribute it to peasant cultivators. Although there could be a major roll back of changes in land tenure, the leader of the Constitutionalists and now President, Venustiano Carranza, was both a politician and large land owner, who was unwilling implement land reform. The state's power regarding subsoil rights meant that the mining and petroleum industries that were developed and owned by foreign industrialists now had less secure title to their enterprises. The industrial sector of Mexico escaped the destruction of revolutionary violence and many Mexican and foreign industrialists remained in Mexico, but the uncertainty and risk of new investments in Mexican industry meant that it did not expand in the immediate post-Revolutionary period. An empowered labor movement with constitutionally guaranteed rights was a new factor industrialists also had to deal with. However, despite the protections of organized labor's rights to fair wages and working conditions, the constitution restricted laborers' ability to emigrate to the U.S. to work. It "required each Mexican to have a labor contract signed by municipal authories and the consulate of the country where they intended to work." Since "U.S. law prohibited offering contracts to foreign laborers before they entered the United States," Mexicans migrating without a permission from Mexico did so illegally.