The power of exclusion of foreigners being an incident of sovereignty belonging to the government of the United States as a part of those sovereign powers delegated by the constitution, the right to its exercise at any time when, in the judgment of the government, the interests of the country require it, cannot be granted away or restrained on behalf of any one. The powers of government are delegated in trust to the United States, and are incapable of transfer to any other parties. They cannot be abandoned or surrendered. Nor can their exercise be hampered, when needed for the public good, by any considerations of private interest. The exercise of these public trusts is not the subject of barter or contract. Whatever license, therefore, Chinese laborers may have obtained, previous to the act of October 1, 1888, to return to the United States after their departure, is held at the will of the government, revocable at any time, at its bleasure. Whether a proper consideration by our government of its previous laws, or a proper respect for the nation whose subjects are affected by its action, ought to have qualified its inhibition, and made it applicable only to persons departing from the country after the passage of the act, are not questions for judicial determination.