Assess the causes, achievements and limits of superpower detente in the 1970s, and explain why tensions revived by the end of the decade

What this dot point is asking

SEAB wants you to assess the causes, achievements and limits of detente, the relaxation of superpower tensions in the 1970s, and to explain why confrontation revived by the end of the decade. The analytical task is to judge how genuine the relaxation was, which requires distinguishing the spheres in which tensions eased from those in which the contest continued. A strong answer shows that detente eased the nuclear danger while leaving the underlying rivalry intact, which is why it was always fragile.

The answer

Why detente happened: the motives

Detente arose because both superpowers had reasons to manage their rivalry more cautiously. The Cuban Missile Crisis had shown how close confrontation could come to catastrophe, making arms control attractive to both. The arms race had become enormously expensive, and both economies felt the strain, with the Soviet economy in particular struggling to sustain the burden. The United States, exhausted and divided by the Vietnam War, sought to reduce its global commitments. China's split with the Soviet Union opened the way for American diplomacy with Beijing, which gave Washington leverage and Moscow an incentive to improve relations with the West. Detente was thus driven by mutual exhaustion and prudence as much as by any genuine reconciliation.

The achievements

Detente produced real results, especially in arms control and European security. The superpowers negotiated agreements to limit strategic nuclear weapons, slowing the most dangerous part of the arms race and accepting a degree of nuclear parity. In 1975 the Helsinki Accords brought together many states to recognise the existing borders of postwar Europe, to commit to cooperation, and, notably, to affirm human rights, a clause that would later be used by dissidents in the Eastern bloc. There was expanded trade and contact between the blocs. These achievements genuinely reduced the risk of nuclear war and stabilised the central front in Europe.

The limits

Detente was always partial. It eased the nuclear arms race and stabilised Europe, but it did not end the ideological contest or the competition for influence in the wider world. Each superpower understood detente differently. The United States expected it to mean mutual restraint, including in the Third World. The Soviet Union understood it as compatible with continued support for revolutionary and socialist movements, which it did not regard as a breach. This fundamental mismatch meant that detente at the centre coexisted with continued rivalry at the periphery, a contradiction that eventually destroyed it.

Why tensions revived

By the end of the 1970s detente had broken down. Continued superpower competition in the Third World, including Soviet involvement in various regional conflicts, convinced many in the United States that the Soviet Union was exploiting detente to expand. The Soviet intervention in Afghanistan at the end of the decade was the decisive blow, hardening Western opinion and prompting a sharp American response. Within the United States, critics had long argued that detente conceded too much, and the political mood shifted toward renewed confrontation, which fed into the more assertive policies of the early 1980s. The very limits of detente, its failure to constrain the wider contest, thus produced its collapse.

Examples in context

Example 1. The Helsinki Accords and their unintended effect. The 1975 Helsinki Accords are the clearest emblem of detente, recognising postwar European borders and committing the signatories to cooperation. Their human-rights provisions, intended as a modest concession, were later seized upon by dissident movements in the Eastern bloc to hold their governments to account. This unintended consequence shows how an instrument of detente could become a long-term solvent of the Soviet system, linking the 1970s to the eventual end of the Cold War.

Example 2. Afghanistan as the breaking point. The Soviet intervention in Afghanistan at the end of the 1970s is the event most often used to date the collapse of detente. It hardened Western opinion, convinced critics that the Soviet Union had exploited detente to expand, and prompted a sharp American response that fed into the more confrontational policies of the early 1980s. It is the key piece of evidence for explaining why detente did not last.

Try this

Q1. State two achievements of detente. [4 marks]

• Cue. Any two of: strategic arms-control agreements limiting nuclear weapons; the 1975 Helsinki Accords recognising European borders and affirming human rights; expanded trade and contact between the blocs.

Q2. Explain why the superpowers pursued detente in the 1970s. [12 marks]

• Cue. The shock of the Cuban Missile Crisis, the cost of the arms race, economic strain, American exhaustion after Vietnam, and the opening to China all encouraged a more cautious, managed rivalry.

Q3. "Detente was doomed from the start." How far do you agree? [20 marks]

• Cue. Argue that the divergent definitions and the failure to constrain the Third World contest built in fragility; weigh against the genuine arms-control and Helsinki achievements; judge.