History · A Level: The nuclear arms race, 1945-1991 (exams to Nov 2026). The idea in plain words, the rules to remember, the mistake to avoid and a worked example, written and checked by Mega Lecture.
Nuclear weapons made a direct war between the superpowers too dangerous. This is deterrence. Rivalry continued in other forms: proxy wars, spying, the space race and tests of nerve called brinkmanship, as over Berlin and Cuba.
The arms race also raised fear and mistrust. The shock of Cuba in 1962 pushed both sides towards arms control, and the USSR built up to rough parity with the USA by about 1970.
A new round began in the late 1970s with Soviet SS-20s and, in reply, US Pershing II and cruise missiles in Europe. Reagan's SDI then threatened to upset the balance that MAD rested on.
Do not write that the arms race only made relations worse. It caused fear and crises, but it also kept the superpowers from fighting each other directly and gave them a reason to negotiate.
Answer: SDI threatened the Soviet ability to retaliate, so it weakened deterrence and forced a costly new stage of the arms race.
Type what you are stuck on. The helper finds the explanation, worked examples and the notes to read, free and instant.
← The development of the nuclear arms raceAttempts to control nuclear weapons →Take a History test