Final answer:
The necessity of forming political bodies and granting power to rulers in the West is primarily associated with maintaining law and order, protecting individual rights and freedoms, ensuring efficient governance, and establishing justice and equality.
Step-by-step explanation:
According to Western political thought, the necessity of forming political bodies and granting power to rulers arises primarily from the need for maintaining law and order within a society. This concept is rooted in historical recognitions that protection and the resolution of conflicts were easier when groups stayed together and designated authorities to go over the rest. Not only do governments provide the essential function of protecting their citizens, but they also serve to protect individuals' rights and freedoms. Moreover, the requirement for efficient governance and decision-making becomes evident as societies grow in complexity, necessitating organized systems to manage collective issues. Finally, there is the aspiration to establish a system of justice and equality, which together with the protection of rights and the need for efficiency, underpins the legitimacy of a government.
Historical rulers claimed authority through various sources such as divine rule, and new political ideologies like liberalism and socialism have shaped the understanding of a government's role in regard to individual freedoms and distribution of resources. The concepts of sovereignty and social contract theory have advanced the idea that governments gain legitimacy and the right to rule through the collective assent of the governed, with an implied agreement that rulers should act in the service of the common good.