of nuclear arsenals, the proposed START treaty would require both sides to reduce their existing nuclear arsenals. In March 1983, Reagan introduced the Strategic Defense Initiative (SDI), 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. Many scientists and national security experts criticized the project as costly and technologically infeasible, and critics dubbed SDI as "Star Wars" in reference to a popular film series of the same name. Ultimately, the SDI would be canceled in 1993 due to concerns about its cost and effectiveness as well as a changing international situation. However, the Soviets became concerned about the possible effects SDI would have and viewed its development as a violation of the Anti-Ballistic Missile Treaty. In protest of SDI, the Soviet Union broke off arms control talks, and U.S.-Soviet relations descended to their lowest point since the early 1960s. The Cold War tensions influenced works of popular culture such as the films The Day After and WarGames (both 1983), and the song "99 Luftballons" (1983) by Nena, each of which exhibited the rising public anxiety for the possibility of a nuclear war. Reagan Doctrine Under a policy that came to be known as the Reagan Doctrine, the Reagan administration 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. In Eastern Europe, the CIA provided support to the Polish opposition group, Solidarity, ensuring that it stayed afloat during a period of martial law. Reagan deployed the CIA's Special Activities Division to Afghanistan and Pakistan, and the CIA was instrumental in training, equipping, and leading Mujahideen forces against the Soviet Army in the Soviet–Afghan War. By 1987, the United States was sending over $600 million a year, as well as weapons, intelligence, and combat expertise to Afghanistan. The Soviet Union announced it would withdraw from Afghanistan in 1987, but the U.S. was subjected to blowback in the form of the Taliban and al-Qaeda, two groups that arose out of the Mujahideen and that would oppose the United States in future conflicts. Although leading conservatives argued that Reagan's foreign policy strategy was essential to protecting their security interests, critics labeled the initiatives as aggressive and imperialistic, and chided them as "warmongering". Reagan was also