Final answer:
The invention of mini-A bombs and the development of nuclear arsenal during the Cold War was driven by the need for powerful strategic weapons, deterrence through the doctrine of Mutually Assured Destruction, and public preparedness for potential attacks. The Manhattan Project was a critical start in this arms race, with notable scientists contributing to the development of the world's first nuclear bombs.
Step-by-step explanation:
The development of a mini-A bomb by the government can be traced back to the escalating arms race and the need for strategic military weapons during and after World War II. Countries invested greatly in nuclear research, driven by the fear of other nations developing more powerful weapons and the need for defense through deterrence, a principle encapsulated in the doctrine of Mutually Assured Destruction (MAD). The U.S. initiated the Manhattan Project in response to threats of nuclear weapons development by Axis powers, which included world-renowned physicists such as J. Robert Oppenheimer and even contributions from individuals like Albert Einstein.
As nuclear technology advanced, governments directed extensive resources towards creating more sophisticated and powerful bombs, with some reaching explosive yields of up to 20 million tonnes of TNT. These advancements were not solely for offensive purposes but also acted as a deterrent against possible Soviet aggression during the Cold War, with possession of a sizeable nuclear arsenal viewed as a defensive measure. Versatile in their use, these weapons ranged from tactical nukes to the larger thermonuclear weapons that characterized Cold War arsenals.
While the creation of atomic bombs was primarily for military use, part of the effort also involved preparing the public for potential nuclear attacks. Instructions on building bomb shelters, identification practices, and educational films like 'Duck and Cover' were produced to mentally equip the public for such eventualities, embedding the notion that survival was possible and thereby managing civilian morale and panic.