Since 1940 UK and USA have been close military allies appreciating the Special Relationship built as period of war allies and NATO partners. In December 1938, UK discovered nuclear fission and British considered producing an atomic bomb without American help is not possible for them as The United Kingdom did not have the manpower or resources of the United States best counterfeit id. In July 1940, Britain signed the Quebec Agreement, which unified the two national projects, forming a united front against the Soviet Union. Britain backed the Manhattan Project by helping initiate the effort to construct the first atomic bombs in the United States during World War II, and helped carry it through to achievement in August 1945 by supplying crucial expertise. This assistance of UK to USA was clear threat to USSR as UK supporting USA as an ally became an enemy to USSR as enemies ally is considered as enemy in international system resultantly on August 29, 1949 soviet developed its nuclear weapon leading security threat to USA as well as UK .With the Soviet Union's first atomic bomb test the 'Cold War' nuclear arms race between the USSR and the United States was on, which became a clear threat to UK as the world was divided into two part after word war 2 , one side dominated by US and other part by USSR best counterfeit id, the cold war became a war of alliance rather than US USSR war and UK being ally which supported USA nuclear program became on the red list of USSR .
The British government had trusted that America would share nuclear technology, which it considered a joint discovery. British aspirations were quickly dashed when the United States limited participation to basic scientific study. The United States did not follow through on its promise to assist the United Kingdom in the design, construction, and operation of an atomic power plant. The Atomic Energy Act of 1946 put a stop to technical collaboration by restricting access to "restricted data," which prohibited the US allies from getting any knowledge. Americans now have distrust about British security systems. As a result, American cooperation has come to an end .This end of cooperation of USA with UK became a betrayal for UK furthermore increasing UK to have security concerns from USSR as well as US .The end of American cooperation Caused serious threat to UK from both super powers the USA which could anytime suppress UK and nuclear umbrella is not sure as US will not sacrifice New York for any other state. This betrayal of USA became a security threat to UK as the British had contributed to the successful creation of an atomic bomb, and yet after the war were faced with the reality that they had been cut off from its secrets, thus according to Scott Sagan a state go nuclear when it feels threat to it security same UK did by acquiring its nuclear weapon On 3 October 1952, the United Kingdom became the third country to test nuclear weapons after the United States and the Soviet Union.
To comprehend the UK's nuclear program, we must first comprehend the country's past. The United Kingdom enjoyed a prosperous time period in the twentieth century known as Great Britain. Great Britain held territory in several parts of the world. Canada, South Asia, a few countries in Africa, and Australia were all British colonies. While World War I did not bring the kingdom of Great Britain to an end, WWII significantly harmed the country. In the 1940s, the United Kingdom began disintegrating and its colonies gained independence. On the other side, the USA began the Manhattan project with the UK as a partner, but after the project's success, the USA cut ties with the UK and said that it would not transmit nuclear information relating to nuclear weapons. The United Kingdom began developing nuclear weapons and testing them on Australian soil. In 1952, the United Kingdom declared its nuclear capability.
The Sagan model of norms was applied to the case study of the United Kingdom because the country has never faced a direct threat from another country but has enjoyed the liberty to rule over various parts of the world. However, without their colonies, the United Kingdom lacked strategic relevance in the world. The UK has a tiny land mass in comparison to other superpowers. It was a problem with the UK's social norms that resulted in the development of their nuclear weapon. The USA and USSTR were developing following WWII, and the UK lacked global influence. Thus, the UK pursued the nuclear program in order to maintain their strategic relevance and to maintain their status as a significant power in the future. The UK's vanity drove them to pursue a nuclear weapons program, which they eventually accomplished. The norms were critical in this case because the nature of the British people became dominant after capturing various territories throughout the world, and they desired to maintain that relevance in the future.