Final answer:
Nuclear weapon storage and security requirements are outlined in international treaties such as START and the NPT, aimed to control nuclear proliferation especially after the dissolution of the Soviet Union.
Step-by-step explanation:
Requirements for nuclear weapon storage and security can be located in various international agreements and organizations that aim to control nuclear proliferation. Treaties like the Strategic Arms Reduction Treaty (START) and the Nuclear Non-Proliferation Treaty (NPT) have been pivotal in setting the guidelines for the reduction of arms stockpiles and restricting nuclear activities to prevent the spread of nuclear weapons capabilities. The collapse of the Soviet Union heightened concerns about the security of nuclear weapons, leading to efforts like the denuclearization of states like Ukraine, Kazakhstan, and Belarus, which possessed nuclear weapons after the disintegration of the USSR.
Additionally, there are concerns about the availability of fissionable material and the capability of small countries and non-state actors, including terrorist groups, to create nuclear weapons. The control and accountability over fissionable material are critical to ensure that these groups do not gain access to nuclear weapons, as a small amount of such material is enough to make a crude bomb. The danger of nuclear technology falling into the hands of rogue states and terrorist organizations continues to be a major threat to international security.