Intermediate-range ballistic missile in the context of "Strategic Rocket Forces"

The PGM-17A Thor was the first operative ballistic missile of the United States Air Force (USAF). It was named after the Norse god of thunder. It was deployed in the United Kingdom between 1959 and September 1963 as an intermediate-range ballistic missile (IRBM) with thermonuclear warheads. Thor was 65 feet (20 m) in height and 8 feet (2.4 m) in diameter.

The first generation of Thor missiles were rushed into service, and design mistakes resulted in a 24% launch failure rate. The competing PGM-19 Jupiter missile saw more use, but both were quickly eclipsed by the Air Force's long range ICBM program, which could be fired from U.S. soil. By 1959, with the Atlas missile well on its way to operational status, both Thor and Jupiter programs became obsolete as delivery vehicles, yet continued to be built and deployed until 1963 for political reasons and to maintain aerospace industry employment.

Project Emily was the deployment of American-built Thor intermediate-range ballistic missiles (IRBMs) in the United Kingdom between 1959 and 1963. Royal Air Force (RAF) Bomber Command operated 60 Thor missiles, dispersed to 20 RAF air stations, as part of the British nuclear deterrent.

Due to concerns over the buildup of Soviet missiles, US President Dwight D. Eisenhower met Prime Minister Harold Macmillan in Bermuda in March 1957 to explore the possibility of short-term deployment of IRBMs in the United Kingdom until the long-range intercontinental ballistic missiles (ICBMs) were deployed. The October 1957 Sputnik crisis caused this plan to be expedited. The first Thor missile arrived in the UK on a Douglas C-124 Globemaster II transport aircraft in August 1958, and was delivered to the RAF in September.

Wernher Magnus Maximilian Freiherr von Braun (US: /ˈvɜːrnər vɒn ˈbraʊn/ VUR-nər von BROWN; German: [ˈvɛʁnheːɐ̯ fɔn ˈbʁaʊn]; 23 March 1912 – 16 June 1977) was a German-American aerospace engineer and space architect. He was a member of the Nazi Party and later the Allgemeine SS which supported his rocket work. He became the leading figure in the development of rocket technology in Nazi Germany, and later a pioneer of rocket and space technology in the US.

As a young man, von Braun worked in Nazi Germany's rocket development program. He helped design and co-developed the V-2 rocket at Peenemünde Army Research Center during World War II. The V-2 became the first artificial object to travel into space by crossing the Kármán line on 20 June 1944. Following the war, he was secretly moved to the United States, along with about 1,600 other German scientists, engineers, and technicians, as part of Operation Paperclip. He worked for the United States Army on an intermediate-range ballistic missile program, and he developed the rockets that launched the United States' first space satellite Explorer 1 in 1958. He worked with Walt Disney on a series of films, which popularized the idea of human space travel in the US and beyond from 1955 to 1957.

Thor was a US space launch vehicle derived from the PGM-17 Thor intermediate-range ballistic missile. The Thor rocket was the first member of the Delta rocket family of space launch vehicles. The last launch of a direct derivative of the Thor missile occurred in 2018 as the first stage of the final Delta II.

A missile launch facility, also known as an underground missile silo, launch facility (LF), or nuclear silo, is a vertical cylindrical structure constructed underground, for the storage and launching of intercontinental ballistic missiles (ICBMs), intermediate-range ballistic missiles (IRBMs), or medium-range ballistic missiles (MRBMs). Similar facilities can be used for anti-ballistic missiles (ABMs).

The structures typically have the missile some distance below ground, protected by a large "blast door" on top. They are usually connected, physically and/or electronically, to a missile launch control center.

In nuclear strategy, a first strike or preemptive strike is a preemptive surprise attack employing overwhelming force. First strike capability is an attacking country's ability to significantly cripple another nuclear power's second strike retaliatory capacity. The preferred methodology is to attack the opponent's strategic nuclear weapon facilities (missile silos, submarine bases, bomber airfields), command and control sites (a decapitation strike), and storage depots first. The strategy is called counterforce.

During the 1950s, first strike strategy required strategic bomber sorties taking place over hours and days. In the 1960s, the deployment of intercontinental ballistic missiles cut the first strike duration to 30 minutes. Also during the Cold War, medium- and intermediate-range ballistic missiles, such as those involved in the Cuban Missile Crisis and Euromissile Crisis, as well as submarine-launched ballistic missiles, reduced the time even further, often below 10 minutes.