- Signed: 18 June 1979
- Entered into Force: Never entered into force; superseded by the START I Treaty in 1991
- Duration: Until 31 December 1985; unless the Treaty is replaced earlier by an agreement further limiting strategic offensive arms
- Parties: Soviet Union and United States
As mandated by Article VII of SALT I, in November 1972, the Parties began negotiations on further limitations on offensive strategic arms. The primary goal of SALT II was to replace the Interim Agreement with a long-term comprehensive treaty on broad limitations on strategic offensive weapons. The Parties discussed what types of weapons should be included, prohibitions on new systems, qualitative limitations, inclusion in the treaty of the US forward-based systems, etc. In November 1974, the Parties reached a basic framework for SALT II, which included:
- 2,400 equal aggregate limit on strategic nuclear delivery vehicles (SNDV), including intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and heavy bombers;
- 1,320 equal aggregate limit on multiple independently targetable re-entry vehicle (MIRV) systems;
- prohibition on construction of new land-based ICBM launchers;
- limits on deployment of new types of strategic offensive arms;
- duration of the new Treaty should be until 1985.
After further intensive work on several levels, the Parties signed the SALT II Treaty on 18 June 1979. In 1991, the Treaty was superseded by START I.
The Treaty obligated the Parties to limit strategic offensive arms quantitatively and qualitatively, to exercise restraint in the development of new types of strategic offensive arms, and to adopt other measures provided for in the Treaty (Article I). Upon entry into force of the Treaty, the Parties undertook to limit ICBM launchers, SLBM launchers, heavy bombers, and air-to-surface ballistic missiles (ASBMs) to an aggregate number not to exceed 2,400, and from 1 January 1981, to an aggregate number not to exceed 2,250, as well as to initiate reductions of those arms, which as of that date would be in excess of this aggregate number (Article II and III). These limitations did not apply to ICBM and SLBM test and training launchers or to space vehicle launchers for exploration and use of outer space (Article VII). Within these aggregate numbers, the Parties were entitled to determine the composition of these aggregates (Article III).
The Parties undertook not to start construction of additional fixed ICBM launchers; not to relocate fixed ICBM launchers; not to convert launchers of light ICBMs or of ICBMs of older types deployed prior to 1964 into launchers of heavy ICBMs of types deployed after that time; in the process of modernization and replacement of ICBM silo launchers, not to increase the original internal volume of an ICBM silo launcher by more than 32 percent; not to supply ICBM launcher deployment areas with ICBMs in excess of a number consistent with normal deployment, maintenance, training, and replacement requirements; not to provide storage facilities for or to store ICBMs in excess of normal deployment requirements at launch sites of ICBM launchers ("normal deployment requirements" means the deployment of one missile at each ICBM launcher); not to develop, test, or deploy systems for rapid reload of ICBM launchers; not to have under construction at any time ICBM launchers, SLBM launchers, heavy bombers, and ASBMs in excess of numbers consistent with a normal construction schedule; not to develop, test, or deploy ICBMs with a launch-weight or a throw-weight greater than that of the heaviest of the heavy ICBMs deployed by either Party as of the date of signature of this Treaty; not to convert land-based launchers of ballistic missiles that are not ICBMs into launchers for launching ICBMs, and not to test them for this purpose; not to flight-test or deploy new types of ICBMs, that is, types of ICBMs not flight-tested as of 1 May 1979, (except that each Party may flight-test and deploy one new type of light ICBM); not to flight-test or deploy ICBMs of a type flight-tested as of 1 May 1979 with a number of re-entry vehicles greater than the maximum number of re-entry vehicles, with which an ICBM of that type has been flight-tested as of that date; not to flight-test or deploy ICBMs of the one new type permitted by the Treaty with a number of re-entry vehicles greater than the maximum number of re-entry vehicles, with which an ICBM of either Party has been flight-tested as of 1 May 1979, (that is, 10); not to flight-test or deploy SLBMs with a number of re-entry vehicles greater than the maximum number of re-entry vehicles with which an SLBM of either Party has been flight-tested as of 1 May 1979, (that is, 14); not to flight-test or deploy ASBMs with a number of reentry vehicles greater than the maximum number of re-entry vehicles with which an ICBM of either Party has been flight-tested as of 1 May 1979, (that is, 10); not to deploy at any one time on heavy bombers equipped for cruise missiles capable of a range in excess of 600 kilometers (km) more than 28 such cruise missiles (Article IV).
Within the aggregate limits, the Treaty set the following sub-limits:
- Total of 1,320 launchers of ICBMs and SLBMs equipped with MIRVs, ASBMs equipped with MIRVs, and heavy bombers equipped for cruise missiles capable of a range in excess of 600 km.
- Total of 1,200 launchers of ICBMs and SLBMs equipped with MIRVs, and ASBMs equipped with MIRVs
- Total of 820 launchers of ICBMs equipped with MIRVs (Article V)
The Treaty prohibited the flight-testing, including research and development, of cruise missiles capable of a range in excess of 600 km or ASBMs from aircraft other than bombers. It also prohibited the conversion of such aircraft into aircraft equipped for such missiles and the conversion of an aircraft other than bombers into an aircraft, which can carry out the mission of a heavy bomber (Article VII).
The Treaty prohibited development, testing, or deployment of ballistic missiles capable of a range in excess of 600 km for installation on waterborne vehicles other than submarines, or launchers of such missiles; fixed ballistic or cruise missile launchers for emplacement on the ocean floor, on the seabed, or on the beds of internal waters and inland waters, or in the subsoil thereof, or mobile launchers of such missiles that move only in contact with the ocean floor, the seabed, or the beds of internal waters and inland waters, or missiles for such launchers; systems for placing into Earth orbit nuclear weapons or any other kind of WMD, including fractional orbital missiles; mobile launchers of heavy ICBMs; SLBMs that have a launch-weight greater or a throw-weight greater than that of the heaviest of the light ICBMs deployed by either Party as of the date of signature of the Treaty, or launchers of such SLBMs; ASBMs that have a launch-weight greater or a throw-weight greater than that of the heaviest of the light ICBMs deployed by either Party as of the date of signature of the Treaty (Article IX).
The Treaty allowed modernization and replacement of strategic offensive arms, subject to the provisions of the Treaty, and obligated the Parties to dismantle or destroy strategic offensive arms in excess of the Treaty's aggregate numbers by 31 December 1981 and strategic offensive arms prohibited by the Treaty no later than six months after the entry into force of this Treaty (Articles X and XI).
The Parties undertook to begin, promptly after the entry into force of this Treaty, active negotiations with the objective of achieving, as soon as possible, agreement on further measures for the limitation and reduction of strategic arms (Article XIV); The Treaty provided for the use of the Standing Consultative Commission (SCC) established by the Memorandum of Understanding between the Parties on 21 December 1972, which was assigned with multiple tasks in order to promote the objectives and implementation of the provisions of the Treaty.
Verification and Compliance
SALT II entitled the Parties to use their national technical means (NTM) of verification to ensure compliance with the Treaty and obligated them not to interfere with NTM of the other Party, as well as not to use deliberate concealment measures that may impede verification by NTM (Article XV). The Treaty provided for notifications on a case-by-case basis of ICBM launches, except for single ICBM launches from test ranges or from ICBM launcher deployment areas, which were not intended to extend beyond a Party's national territory (Article XVI).
No mechanisms existed to deal with non-compliance.
The Treaty allowed the Parties to withdraw from the Treaty, with a six-month notice, if they decided that extraordinary events related to the subject matter of the Treaty had jeopardized their supreme interests.
The Treaty was supplemented with numerous Agreed Statements and Common Understandings elaborating on specific provisions of the Treaty or defining specific terms used in the Treaty's language.
Protocol to the Treaty
The Parties also signed a Protocol to the Treaty, in which they agreed to additional limitations. The Parties undertook not to deploy mobile ICBM launchers or to flight-test ICBMs for such launchers; not to deploy cruise missiles capable of a range in excess of 600 km on sea-based launchers or on land-based launchers; not to flight-test cruise missiles capable of a range in excess of 600 km that are equipped with multiple independently targetable warheads from sea-based or land-based launchers; and not to flight-test or deploy ASBMs. The Protocol was also supplemented with Agreed Statements and Common Understandings elaborating on its specific provisions or defining specific terms.
Memorandum of Understanding
The Parties also exchanged initial declarations on the number of strategic offensive arms they possessed and agreed to maintain this agreed database through regular updates at each session of the SCC. They made a joint statement on principles and guidelines for subsequent negotiations on the limitation of strategic arms. The Parties agreed to pursue negotiations on further quantitative and qualitative limitations on strategic arms, to apply additional verification measures to increase effectiveness of NTM, and to take other steps to ensure and enhance strategic stability and equal security of the Parties.
The USSR made a unilateral statement regarding its "Tu-22M" (Backfire) bomber, which it declared to be a medium-range bomber and did not intend to give the bomber the capability of operating at intercontinental distances.
The Treaty was superseded by the START I Treaty.
On 18 July, the USSR destroyed missile launchers and declared again that it was continuing within the Treaty's limits. The Soviet Ministry of Defense presented figures indicating that the USSR SNDVs totaled 2,484 (2,504 max) in 1990. The United States claimed the real Soviet SNDV figure was 2,580, while the United States maintained a total of 1985 SNDVs (2,250 max).
SALT II proponents in the United States relied on budget limits to keep the United States from further exceeding the limits.
At the end of 1989, the United States had exceeded the MIRVed ICBMs + MIRVed SLBMs + bombers with ALCMs limit of 1,320 by 61, while the USSR remained under all sub-limits, but over the 2,250 total SNDV limit.
The US House passed language putting the 820/1,200/1,320 sub-limits into law; however, the Senate did not pass such language. Therefore, the conference abandoned the language but noted that, for budgetary reasons, the US strategic forces would be stabilized during FY89 at roughly the same levels as FY88.
During 1987, the USSR apparently continued to abide by the limits. In the United States, the Congress and the administration agreed that the United States would stay under the SLBM and ICBM sub-limits, although President Reagan was strongly opposed to it.
On 27 May, President Reagan announced that the United States would no longer abide by the Treaty limits. The president said that the USSR was not observing its political commitment to observe provisions of the Treaty, as well as not demonstrating its readiness to achieve further arms reductions agreements. He continued that the United States would base its decisions regarding its strategic force structure on the nature and magnitude of the threat posed by Soviet strategic forces and not on standards contained in the SALT structure. He stated that the United States would not deploy more SNDV or strategic ballistic missile warheads than the USSR in order to protect strategic deterrence.
On 28 May, the United States announced that it would continue equipping B-52s with ALCMs beyond the limit of 130.
On 28 November, the United States exceeded the 1,320 SNDV limit. On 5 December, the USSR announced that it would abide by the limits for the time being.
The United States repeated its January 1984 accusation of the USSR's violations of certain provisions of the Treaty. In June, President Reagan reaffirmed that it was in the United States' interest to maintain an interim framework of mutual restraint with the USSR and declared that the United States would continue to refrain from undercutting existing strategic arms agreements as long as the USSR exercised comparable restraint and actively pursued arms reductions agreements in the Nuclear and Space Talks (NST) in Geneva. The USSR also restated its January 1984 accusations of US violations of certain provisions of the Treaty.
On 23 January, the United States stated that the USSR had violated its political commitment to observe the provisions of the Treaty on encrypting telemetry and modernization of ICBMs, as well as "probably" violated the ban on deployment of the SS-16 and the provision permitting only one new type of ICBM. Based on that, President Reagan openly considered American abrogation of the still not ratified Treaty.
On 27 January, the USSR stated that the United States had in turn violated its political commitment to observe the provisions of the Treaty on negotiating a ban on SLCMs and ground-launched cruise missiles (GLCMs), on non-circumvention by deploying the GLCM and Pershing II, and also intended to violate the provision permitting only one new type of ICBM.
On 17 July, the US Air Force conducted the first test-flight of the Peacekeeper (MX) four-stage ICBM capable of carrying up to 10 independently targeted re-entry vehicles.
In May 1, US President Reagan stated he would not do anything to undercut the Treaty as long as the USSR demonstrated equal restraint. The USSR made a statement along similar lines.
The United States announced that it would not ratify the Treaty, leaving the Parties under only a political obligation to abide by the Treaty limits.
In response to the December 1979 Soviet invasion of Afghanistan, on 3 January, President Carter requested that the Senate delay consideration of the Treaty. The US President declared that the United States would comply with the Treaty as long as the USSR reciprocated. Soviet General Secretary Brezhnev made a similar statement regarding Soviet intentions. The Parties, therefore, undertook to refrain from acts, which would defeat the object and purpose of the Treaty, until one of them had made its intentions clear not to become a party to the Treaty.
On 22 June, President Carter transmitted the Treaty to the Senate, where it ran into considerable resistance.
SALT refers to two rounds of talks between the US and the USSR on nuclear arms control. SALT II lasted from 1972-1979.