The Second Cold War: Afghanistan & Reagan’s SDI
The Soviet Invasion of Afghanistan (1979)
In December 1979, the Soviet Union invaded Afghanistan. A communist government had taken power there in 1978, but it faced fierce opposition from Islamic guerrilla fighters known as the mujahideen. When the Afghan government asked for Soviet help, Brezhnev sent over 100,000 troops. He feared that if the communist government fell, it would encourage anti-Soviet movements in the USSR’s own Muslim-majority Central Asian republics.
The Soviet invasion of Afghanistan ended détente and began what historians call the “Second Cold War.” The war lasted ten years (1979–89), cost over 15,000 Soviet soldiers’ lives, and is often compared to America’s experience in Vietnam — a costly, unwinnable guerrilla war.
The USA saw the invasion as Soviet aggression and expansionism. President Carter’s national security adviser Zbigniew Brzezinski warned that the USSR might be trying to reach the oil-rich Persian Gulf. Whether the invasion was genuinely aggressive or merely defensive (protecting a neighbouring communist government) remains debated by historians.
The Carter Doctrine & Western Response
President Carter responded forcefully to the invasion. In January 1980, he announced the Carter Doctrine, declaring that any attempt by an outside force to gain control of the Persian Gulf region would be regarded as an assault on the vital interests of the USA and would be repelled by military force.
Carter also took a series of punitive measures: he withdrew SALT 2 from Senate consideration, imposed a grain embargo on the USSR (cutting off American wheat exports), and increased US defence spending. Most dramatically, the USA boycotted the 1980 Moscow Olympics, with 64 other nations following suit. The USSR retaliated by boycotting the 1984 Los Angeles Olympics.
The 1980 Moscow boycott was led by the USA and included 64 other nations, though some major countries like Britain and France allowed their athletes to compete under the Olympic flag rather than their national flags. The boycott embarrassed the Soviet Union but did not change its policy in Afghanistan. In retaliation, the USSR and 13 allies boycotted the 1984 Los Angeles Olympics, claiming concerns about “security” for their athletes. The mutual boycotts showed how deeply the Cold War could penetrate even sport.
The USA also began covertly supplying the mujahideen with weapons and money through Pakistan’s intelligence services. This included Stinger anti-aircraft missiles, which proved devastatingly effective against Soviet helicopters. The CIA’s support for the mujahideen was one of the largest covert operations of the Cold War.
Reagan & the “Second Cold War”
In January 1981, Ronald Reagan became US President. He took a far more aggressive stance towards the Soviet Union than Carter had. Reagan believed détente had been a mistake that allowed the USSR to build up its military while the USA relaxed. He called the Soviet Union an “evil empire” and dramatically increased US defence spending — the military budget rose from $178 billion in 1981 to $229 billion by 1985.
Reagan’s strategy was deliberate: he believed the USA could outspend the Soviet Union in an arms race, forcing the USSR to choose between military spending and economic collapse. The Soviet economy, already struggling, could not match American spending.
The Strategic Defence Initiative (SDI / “Star Wars”)
In March 1983, Reagan announced the Strategic Defence Initiative (SDI), nicknamed “Star Wars.” This was a proposed space-based defence system that would use satellites and lasers to shoot down Soviet nuclear missiles before they reached the USA. If it worked, it would make the USA immune to nuclear attack and destroy the principle of Mutually Assured Destruction (MAD).
The Soviet Union was alarmed by SDI. If the USA could defend itself against nuclear attack, the USSR’s entire nuclear arsenal would become useless, and the balance of power would shift decisively in America’s favour. Many scientists doubted SDI was technically feasible, and it was never fully built. However, the threat of SDI was enough to worry the Soviet leadership and pressure them into negotiations. SDI became a major obstacle in arms control talks, as the USSR sought limits on it.
Historians disagree about SDI’s role in ending the Cold War. Some argue that SDI pressured the USSR into negotiations because the Soviet economy could not afford to develop a matching system, ultimately forcing Gorbachev to seek arms reduction deals with the West. Others argue that SDI was never realistic and that the Cold War ended because of the internal weaknesses of the Soviet system and Gorbachev’s own reforms. What is clear is that SDI increased Soviet anxiety and contributed to the sense that the arms race was unsustainable.