The right of the United States, from both the international and constitutional viewpoints, to prohibit entrance within its borders to such aliens as it may deem undesirable additions to its population, has been examined and upheld in numerous cases, most of them dealing with the exclusion of the Chinese.

In the Chinese Exclusion Case,7 decided in 1887, the Supreme Court said: "To preserve its independence, and give security against foreign aggression and encroachment, is the highest duty of every nation, and to attain these ends nearly all other considera-tions are to be subordinated. It matters not in what form such aggression and encroachment come, whether from the foreign nation acting in its national character, or from vast hordes of its people crowding in upon us. The government, possessing the powers which are to be exercised for protection and security, is clothed with authority to determine the occasion on which the powers shall be called forth; and its determination, so far as the subjects affected are concerned, are necessarily conclusive upon all its departments and officers. If, therefore, the government of the United States, through its legislative department, considers the presence of foreigners of a different race in this country, who will not assimilate with us, to be dangerous to its peace and security, their exclusion is not to be stayed because at the time there are no actual hostilities with the nation of which the foreigners are subjects. The existence of war would render the necessity of the proceeding more obvious and pressing. The same necessity, in a less pressing degree, may arise when war does not exist, and the same authority which adjudges the necessity in one case must also determine it in the other. In both cases, its determination is conclusive upon the judiciary. If the government of the country of which the foreigners excluded are subjects is dissatisfied with this action, it can make complaint to the executive head of our government, or resort to any other measure which, in its judgment, its interest or dignity may demand; and there lies its only remedy."

7 Sub nom. Chae Chan Ping v. United States, 130 U. S. 581; 9 Sup. Ct Rep. 623; 32 L. ed. 1068.

In this case the court held that so essential to a State is this right of excluding undesired aliens, the State may not be prevented, even by treaty, from exercising it at its own discretion. Thus, in holding valid an act of Congress the terms of which were in violation of a treaty previously entered into by this country with China, the court said: "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 anyone. 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, 188S, to return to the United States after their departure, is held at the will of the government, revable at any time, at its pleasure. 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. If there be any just ground for complaint on the part of China, it must be made to the political department of our government, which is alone competent to act upon the subject."

This power of exclusion, as the Supreme Court has, in a line of cases, held, may be exercised through executive officers without judicial intervention.8

As we have seen from the foregoing quotations, the same principles that support, constitutionally, the right of the United States to exclude aliens, support the right to expel them when occasion demands. Bonfils states the international doctrine as follows: "A State has the right to expel from its territory aliens, individually or collectively, unless treaty provisions stand in the way. . . . In ancient times, collective expulsion was much practised. In modern times it has been resorted to only in case of war. Some writers have essayed to enumerate the legitimate causes of expulsion. The effort is useless. The reasons may be summed up and condensed in a single word: The public interests of the State. Bluntsohli wished to deny the States the right of expulsion, but he was obliged to acknowledge that aliens might be expelled by a single administrative measure. (French law of December 2, 1849, arts. 7 & 8 - Law of Oct. 19, 1797. art, 7.) An arbitrary expulsion may nevertheless give rise to a diplomatic claim."9

8Ekiu v. United States, l42 U.S.. 861; 12 Sup. Ct. Rep. 336: 35 L. ed. 1146: Fong Yue Ting v. United States, 149 U. S. 698; 13 Sup. Ct. Rep. 1016: 37 L. oil. 905; Leni Moon Sing v. United States, 158 U. S. 586; 15 Sup, Ct Ren. 967: 89 L. ed. 1082; Turner v. William-. 194 U. S. 279; 24 Sup. Ct. Rep. 719; 48 L. ed. 979; United States v. Ju Try. 199 V. 8. MS; 25 Sup. Ct. Rep. 614; 4n L. ed. 1940; chin Low v. United States, 208 U.S.S; 28 Sup. Ct. Rep. 201; 52 L. ed. 369.

9 Manuel du Droit International Public 442: Moore. Digest of International Law, § 550.