Linkage was a foreign policy that was pursued by the United States and championed by Richard Nixon and Henry Kissinger in the 1970s détente, during the Cold War.
The policy aimed to persuade the Soviet Union to co-operate in restraining revolutions in the Third World in return for concessions in nuclear and economic fields.
In that case, an issue of arms control could be addressed and tension diminished, with the status quo being maintained in other strategic areas.
Common understandings of the term are that linkage means leverage – the linking of one event to another in order to maintain bargaining power or pressure on the opposing party involved.
An example of coercive linkage policy would be the US seeking to tie arms control progress to what they thought was acceptable behaviour in the Third World.
By 1971, the newly established Soviet leader Leonid Brezhnev was ready to accept US ideas about relaxing tensions.
The Soviet Union had issues with the Czechoslovakian Communist party in 1968 when their leader, Alexander Dubček, created reforms encouraging free speech and democracy.
Such conflicts forced the Soviets to scale back aggressiveness and "repair [their] image in the wake of the Prague Spring.
[6] Henry Kissinger (US Secretary of State at the time) believed there were areas of congruent interests which would help to regulate competition between the US and the Soviet Union.
[7] During the Presidencies of both Richard Nixon and Gerald Ford, linkage diplomacy was used as a key foreign policy measure.
"[8] Following the signing of the Strategic Arms Limitation Talks (SALT) agreement in 1972, both the US and the Soviet Union agreed to practise mutual restraint.
[9] As a result of this, part of this administrations perception of linkage was to convince Soviet leaders that they would have motivation for moderation, and also punishment for a contradiction of the previous agreements they had signed.
As trade ties between the US and the Soviet Union increased, Kissinger aimed to convert these connections into political advantages.
[3] If the Soviet Union made exceptions to issues they had with US foreign policy, the United States would grant them the most favoured nation (MFN) status.
[3] Decisions were made without the knowledge of William Rogers, who was the secretary of State at the time and responsible for the management of US diplomacy.
This secrecy and conflicting ideas made it difficult to gain concessions and make progress in foreign policy.
Brzezinski believed that the correct answer to Soviet actions in the Third World was a "carefully calibrated policy of simultaneous competition and cooperation of its own, designed to promote a more comprehensive and more reciprocal détente.
"[11] In 1978 Brzezinski strove to link developments in the SALT II negotiations to revised Soviet behaviour in Africa.
After efforts of mediation from the Soviet Union failed, Somalia cut all ties and its friendship treaty with the USSR in 1977.
He suggested that a more suitable approach would be to accept that the US and the Soviet Union have competition, but not link Third World behaviour with important issues such as the SALT agreements.
President Carter did not reject this, but said that the abuse of human rights and involvement in Africa would make it difficult to ratify the SALT agreement.
[13] Another concern was the fall of the Shah in Iran in early 1979, and the perceived inability of the Carter administration to free the American hostages held there.
[3] Carter's national security advisor, Brzezinski, believed that the Soviets found a sense of confidence and were emboldened by the US failure to react strongly to the USSR intervention of the Horn in 1978.
For example, the US wanted ‘unilateral advantage’ in the Middle East but did not involve the Soviet Union in the Egyptian-Israeli peace process.