The standard of living in the 1970s was "extremely spartan" and discontent was rife. Fidel Castro admitted the failures of economic policies in a 1970 speech. In 1975, the OAS lifted its sanctions against Cuba, with the approval of 16 member states, including the U.S. The U.S., however, maintained its own sanctions. In 1979, the U.S. objected to the presence of Soviet combat troops on the island. U.S. forces invaded the Caribbean island of Grenada in 1983, killing nearly two dozen Cuban construction workers and expelling the remainder of the Cuban aid force from the island. During the 1980s, Castro supported Marxist insurgencies in Guatemala, El Salvador and Nicaragua. Cuba gradually withdrew its troops from Angola in 1989–91.