Reasons for Détente, SALT I, and its extent by 1972

What the specification asks for

“Reasons for Détente. SALT talks and treaty. The extent of Détente in 1972.” — examined through causation and significance. Incandio is aligned to specification 4HI1; it is not published by, endorsed by or affiliated with Pearson.

1 · Understand it

Why both sides wanted it, and neither from strength

The United States was spending enormously on Vietnam with half a million troops committed, was internally divided, and faced a balance-of-payments problem that ended dollar convertibility in 1971. Nixon and Kissinger wanted Soviet help in extracting the United States from Vietnam and a foreign policy that cost less.

The USSR had achieved rough parity in intercontinental missiles by about 1970 and could negotiate as an equal for the first time — and could not afford to keep going, with a stagnating economy, agriculture requiring grain imports, and consumer expectations rising. It also faced China: the Sino-Soviet split had produced armed clashes on the Ussuri river in 1969, and Nixon's opening to Beijing, announced in 1971 with a visit in February 1972, created a Soviet incentive to settle with Washington before Washington settled with Beijing.

Europe supplied a third driver. Willy Brandt's Ostpolitik from 1969 produced treaties with Moscow and Warsaw accepting the post-war borders, and a Basic Treaty between the two Germanys in 1972. The German question, which had caused every European crisis since 1945, was being settled by the Germans.

Both sides therefore came to détente from weakness, which is why it is what two overstretched powers do — and why it did not survive their circumstances changing at the end of the decade.

SALT I, May 1972

Nixon went to Moscow in May 1972, the first American president to do so, and signed two agreements. The ABM Treaty limited each side to two anti-ballistic-missile sites, later reduced to one. This looks defensive and is the more important of the two: by guaranteeing that neither side could defend itself, it guaranteed that neither could strike first without being destroyed, which stabilised deterrence.

The Interim Agreement froze the number of intercontinental and submarine-launched ballistic missile LAUNCHERS at existing levels for five years. That word is the whole lesson. The treaty counted launchers and said nothing about warheads, and MIRV technology — multiple independently targetable re-entry vehicles — was already being deployed by the United States and was developed by the USSR during the agreement.

So the number of launchers was capped and the number of warheads rose faster after 1972 than before, from roughly a few thousand each to well over ten thousand on the American side by 1980. An arms-control treaty presided over the fastest expansion of the arsenals in the Cold War, and the reason is a definition.

The extent of détente in 1972

What it achieved: the first treaty limiting strategic weapons; a stabilised deterrent through ABM; the German question settled by Ostpolitik; expanded trade including large American grain sales; the Basic Principles agreement committing both to avoid confrontation; and a working assumption that crises would be managed rather than escalated.

What it did not touch: the ideological competition; the arsenals themselves; the division of Europe, which it confirmed rather than ended; Soviet control of its bloc, unchanged since the Brezhnev Doctrine; and the proxy conflicts, which continued in Vietnam, in the Middle East and, from the mid-1970s, in Angola and the Horn of Africa.

The single technical fact of MIRV is the most economical way to answer a question about how far détente ended the Cold War. It shows that the agreement was real, that it capped what could be counted, and that the competition continued in the space the counting did not reach.

2 · Learn it — the notes

The dates that earn marks

1969

Sino-Soviet clashes on the Ussuri; SALT talks open; Brandt becomes Chancellor. Why this date: Three of détente's causes appear in the same year.

1970–72

Ostpolitik treaties with Moscow and Warsaw; the Basic Treaty between the two Germanys. Why this date: The European settlement that made a superpower settlement possible.

February 1972

Nixon visits Beijing. Why this date: The triangular pressure that accelerated Moscow's willingness to sign three months later.

May 1972

SALT I and the ABM Treaty signed in Moscow. Why this date: The high point of détente, and the moment the launcher/warhead distinction becomes decisive.

The figures, and how far to trust them

• 2, then 1 — Anti-ballistic-missile sites permitted to each side under the ABM Treaty.
• 5 years — The duration of the Interim Agreement's freeze on launchers.
• Launchers, not warheads — What SALT I counted. (This is the strand's decisive technical point and should be stated in those words.)
• About 500,000 — American troops in Vietnam at the peak, one of détente's main causes.

The people to place

• Richard Nixon — First American president to visit Moscow and Beijing; pursued détente as a way of reducing the cost of containment.
• Henry Kissinger — National Security Adviser; designed the triangular approach to Moscow and Beijing.
• Leonid Brezhnev — Signed SALT I; needed trade and grain and faced China on the other frontier.
• Willy Brandt — West German Chancellor whose Ostpolitik settled the German question and made the superpower agreements easier.

How historians disagree

Attributed interpretations, never voiced — the AO4 seam.

• The 'détente was real' reading: SALT and the ABM Treaty were the first genuine limits on strategic weapons, and combined with Ostpolitik they removed the German question and made European war far less likely. Contested by The reading that détente was a tactical pause by two overstretched powers, evidenced by the MIRV expansion under the treaty and by its collapse once circumstances changed at the end of the 1970s..

What students say — and what is actually the case

Not this: SALT I reduced nuclear weapons.

This: It froze launcher numbers and did not limit warheads. MIRV meant the number of warheads rose faster after 1972 than before, which is the fact that answers the extent question.

Not this: Détente ended the Cold War.

This: It confirmed the division of Europe rather than ending it, left the Brezhnev Doctrine untouched, and collapsed at the end of the decade. It is the Cold War managed, not concluded.

Two things students merge

Blurred: Launchers and warheads.

The distinction: A launcher is a missile or a submarine tube; a MIRVed missile carries several independently targeted warheads. SALT counted the first and not the second, and that single definitional choice is why the arsenals grew under an arms-control treaty.

Blurred: The ABM Treaty and the Interim Agreement.

The distinction: The ABM Treaty limits defensive systems permanently; the Interim Agreement freezes offensive launchers for five years. The defensive one turned out to matter more, because it locked in mutual vulnerability.

What a Grade 9 answer holds here

A Grade 9 answer explains détente as what two overstretched powers do, and can prove the limit with one definition. Both came to the table from weakness — Vietnam and the dollar on one side, a stagnating economy and China on the other — and the treaty they signed capped launchers while warheads multiplied, which tells you exactly how much of the competition either was willing to give up.

3 · How it is examined

This strand is genuinely set through: Paper 1 (a) (6 marks — “What impression does the author give about …? You must use Extract A to explain your answer.”); Paper 1 (b) (8 marks — “Explain two effects of … on ….”); Paper 1 (c)(i) or (c)(ii) (16 marks — “'[A statement about the period.]' You may use the following in your answer: • [prompt] • [prompt]. You must also use information of your own. How far do you agree? Explain your answer.”).

What earns marks: MIRV. Naming it and explaining the launcher/warhead distinction answers 'how far did détente end the Cold War' with a technical fact rather than an impression, and it is the single best-value specific in key topic 5.

4 · Prove it — the questions

Answered inside Incandio, where a marker checks what a correct answer must contain and tells you which half was missing. The marking stays in the app; the questions are here.

1. Explain two reasons for Détente. [8 marks · Paper 1 (b)]
2. Explain two effects of SALT I on superpower relations. [8 marks · Paper 1 (b)]
3. Describe two features of SALT I. [8 marks · Paper 1 (b)]
4. 'Détente had ended the Cold War by 1972.' How far do you agree? Explain your answer. [16 marks · Paper 1 (c)(i) or (c)(ii)]
5. 'Détente happened because both superpowers were weak.' How far do you agree? Explain your answer. [16 marks · Paper 1 (c)(i) or (c)(ii)]

Decide it

This lesson feeds a Decide History judgement — a position you commit to, an objection you answer, a criterion you name: Was Détente a thaw or a pause?.

Carry on through the option

• Previous lesson: The Hotline and the treaties of 1963–68
• Key topic 5 · The Thaw and moves towards Détente, 1963–72 · A world divided: superpower relations, 1943–72 · the option's timeline · Incandio History
• The other key topics of A world divided: Reasons for the Cold War · Early developments in the Cold War, 1945–49 · The Cold War in the 1950s · Three crises: Berlin, Cuba and Czechoslovakia