There is, however, little doubt that such persons, although now more usually allowed to remain, during good behaviour, may be expelled, and, if necessary, wholesale, as were Germans from France in 1870. But may such persons be, for good reasons, arrested, or otherwise prevented from leaving the country, as Germans were prevented from leaving France in the earlier days of the Franco-Prussian War? Grotius speaks with approval of such a step being taken, "ad minuendas hostium vires." Bynkershoek, more than a century later, recognises the right of thus acting, "though it is rarely exercised." So the Supreme Court of the United States in _Brown v. United States_ (1814). So Chancellor Kent (1826), and Mr. Manning (1889) is explicit that the arrest in question is lawful, and that "the individuals are prisoners of war." Vattel, is it true (1758), ventures to lay down that-- "Le Souverain qui déclare la guerre ne peut retenir les sujets de ennemi qui se trouvent dans ses états au moment de la déclaration ... en leur permettant d'entrer dans ses terres et d'y séjourner, il leur a promis tacitement toute liberté et toute sûreté pour le retour." And he has been followed by some recent writers. There is, however, I venture to hold, no ground for asserting that this indulgent system is imposed by international law. I am glad, therefore, to find the Attorney-General laying down that-- "for strictly military reasons, any nation is entitled to detain and to intern soldiers found upon the territory at the outbreak of war." And I should be surprised if, under all circumstances, as the learned Attorney-General seems to think probable-- "England would follow, whatever the strict law may be, the humane and chivalrous practice of modern times, and would give to any subjects of a hostile Power who might be found here engaging in civilian pursuits a reasonable time within which to leave for their own country, even although they were under the obligation of entering for service under the enemy's flag." The doctrine of Vattel has, in fact, become less plausible than it was before universal liability to military service had become the rule in most Continental countries. The peaceably engaged foreign resident is now in all probability a trained soldier, and liable to be recalled to the flag of a possible enemy. There may, of course, be considerable practical difficulties in the way of ascertaining the nationality of any given foreigner, and whether he has completed, or evaded, the military training required by the laws of his country. It may also be a question of high policy whether resident enemies would not be a greater danger to this country if they were compelled to remain here, than if they were allowed, or compelled, to depart, possibly to return as invaders.