The development of the United Kingdom’s first nuclear deterrent programme began shortly after the end of World War II, under the leadership of the Labour prime minister Clement Attlee, whose government believed that a nuclear weapon was vital to the security of the nation.
Attlee’s successor, the Conservative prime minister Winston Churchill, oversaw the first test of a British nuclear weapon on October 3, 1952. “Operation Hurricane” involved the detonation of an atomic device in the lagoon of the uninhabited Monte Bello Islands in Western Australia. The test proved a success, and with it the United Kingdom became the world’s third nuclear power after the United States and the Soviet Union.
By 1953, however, the US and the Soviet Union had both successfully tested the second generation of nuclear weapon – hydrogen bombs. These thermonuclear weapons were more powerful than the atomic weapons that the United Kingdom possessed. Thus, the following year, the UK began the development of its own hydrogen bombs, leading eventually in 1957 to “Operation Grapple” – Britain’s first and successful tests of thermonuclear weapons.
Following these tests, the US-UK Mutual Defence Agreement was signed in 1958, which ensured greater cooperation between the two countries on their respective nuclear deterrent programmes. It also allowed the United Kingdom to buy enriched uranium and American-designed weapons from the US, and allowed the US to buy plutonium from the UK – a deal that was beneficial to both sides.
In 1968, the United Kingdom launched its Polaris programme, which provided the first British submarine-based nuclear weapons system. The UK’s current nuclear deterrent programme, Trident, came into service in 1994 and eventually replaced Polaris, which ceased operation in 1996. Since 1998 – when thermonuclear free-fall bombs were decommissioned – Trident been the only nuclear weapons system operating in the United Kingdom.