As a result of the shootdown, and the cause of KAL 007's going astray thought to be inadequacies related to its navigational system, Reagan announced on September 16, 1983, that the Global Positioning System would be made available for civilian use, free of charge, once completed in order to avert similar navigational errors in future. Under a policy that came to be known as the Reagan Doctrine, Reagan and his administration also provided overt and covert aid to anti-communist resistance movements in an effort to "rollback" Soviet-backed communist governments in Africa, Asia, and Latin America. However, in a break from the Carter administration's policy of arming Taiwan under the Taiwan Relations Act, Reagan also agreed with the communist government in China to reduce the sale of arms to Taiwan. Reagan deployed the CIA's Special Activities Division to Afghanistan and Pakistan. They were instrumental in training, equipping and leading Mujahideen forces against the Soviet Army. President Reagan's Covert Action program has been given credit for assisting in ending the Soviet occupation of Afghanistan, though some of the United States funded armaments introduced then would later pose a threat to U.S. troops in the 2001 War in Afghanistan. The CIA also began sharing information with the Iranian government which it was secretly courting. In one instance, in 1982, this practice enabled the government to identify and purge communists from its ministries and to virtually eliminate the pro-Soviet infrastructure in Iran. In March 1983, Reagan introduced the Strategic Defense Initiative, a defense project that would have used ground- and space-based systems to protect the United States from attack by strategic nuclear ballistic missiles. Reagan believed that this defense shield could make nuclear war impossible. There was much disbelief surrounding the program's scientific feasibility, leading opponents to dub SDI "Star Wars" and argue that its technological objective was unattainable. The Soviets became concerned about the possible effects SDI would have; leader Yuri Andropov said it would put "the entire world in jeopardy." For those reasons, David Gergen, a former aide to President Reagan, believes that in retrospect, SDI hastened the end of the Cold War. Though supported by leading American conservatives who argued that Reagan's foreign policy strategy was essential to protecting U.S. security interests, critics labeled the administration's foreign policy initiatives as aggressive and imperialistic, and chided them as "warmongering." The administration was also heavily criticized for backing anti-communist leaders accused of severe human rights violations, such as Hissène Habré of Chad and Efraín Ríos Montt of Guatemala.