It is the duty of the king or the government to insure that the people observe the social order and that they are also employed in their respective occupational duties. In modern times, since the protection of the government or the king has been withdrawn, social order has practically collapsed. No one knows who is a brahmana, who is a ksatriya, who is a vaisya or who is a sudra, and people claim to belong to a particular social order by birthright only. It is the duty of the government to reestablish social order in terms of occupational duties and the modes of material nature, for that will make the entire world population actually civilized. If it does not observe the institutional functions of the four social orders, human society is no better than animal society in which there is never tranquillity, peace and prosperity but only chaos and confusion. Maharaja Prthu, as an ideal king, strictly observed the maintenance of the Vedic social order. Prajayate iti praja. The word praja refers to one who takes birth. Therefore Prthu Maharaja guaranteed protection for prajanam — all living entities who took birth in his kingdom. Praja refers not only to human beings but also to animals, trees and every other living entity. It is the duty of the king to give all living entities protection and food. The fools and rascals of modern society have no knowledge of the extent of the responsibility of the government. Animals are also citizens of the land in which they happen to be born, and they also have the right to continue their existence at the cost of the Supreme Lord. The disturbance of the animal population by wholesale slaughter produces a catastrophic future reaction for the butcher, his land and his government.

Srila Prabhupada, SB 4.21.22, Purport