Existing contracts between domestic citizens and enemy aliens, which were entered into before war broke out and which were valid at that time, are either suspended or terminated by a declaration of war. They are merely suspended if the delay in performance caused by the war is not so great as materially to affect the burden of the contract, but otherwise they are terminated.7 Where the obligation is a unilateral debt all the ordinary business between people of the same community in buying, selling, and exchanging property, movable and immovable, could be lawfully carried on, except in cases where it was expressly forbidden by the United States, or where it would have been inconsistent with or have tended to weaken their authority. It was commercial intercourse and correspondence between citizens of one belligerent and those of the other, the engaging in traffic between them, which were forbidden by the laws of war and by the President's proclamation of non-intercourse. So long as the war existed, all intercourse between them inconsistent with actual hostilities was unlawful. But commercial intercourse and correspondence of the citizens of the enemy's country among themselves were neither forbidden nor interfered with, so long as they did not impair or tend to impair the supremacy of the national authority or the rights of loyal citizens. No people could long exist without exchanging commodities, and, of course, without buying, selling and contracting. And no belligerent has ever been so imperious and arbitrary as to attempt to forbid the transaction of ordinary business by its enemies among themselves. No principle of public law and no consideration of public policy could be subserved by any edict to that effect; and its enforcement, if made, would be impossible.1' This passage was quoted with approval in Briggs v. United States, 143 U. S. 346, 352,12 S. Ct. 391, 36 L. Ed. 180.
5 Briggs v. United States, 143 U. S. 346, 12 S. Ct. 391, 36 L. Ed. 180.
7 The matter was considered in New York Life Ins. Co. v. Statham, 93 U. S. 24, 23 L. Ed. 789, where the court held the policy of insurance in question was not revived, saying: "The truth owed to an enemy, the obligation is merely suspended.8 As the enemy is excluded from suing, this rule of procedure as well as the rule of substantive law suspending his rights prevents any immediate enforcement of the debt.9 But though an alien enemy is disabled from recovering a debt he may, nevertheless, be sued if a citizen can obtain service of process or attach property belonging to him upon which the government does not exercise its right of seizure.10 is that the doctrine of the revival of contracts suspended during the war is one based on consideration of equity and justice, and cannot be invoked to revive a contract which it would be unjust or inequitable to revive. In the case of life insurance, besides the materiality of time in the performance of the contract, another strong reason exists why the policy should not be revived. The parties do not stand on equal ground in reference to such a revival. It would operate most unjustly against the company." The court added with reference to the contract before it: "Failure being caused by a public war, without the fault of the assured, they are entitled ex ctquo et bono to recover the equitable value of the policies with interest from the close of the war."
8 In Hanger v. Abbott, 6 Wall. 532, 18 L. Ed. 939, the court said: "In former times the right to confiscate debts was admitted as an acknowledged doctrine of the law of nations, and in strictness it may still be said to exist, but it may well be considered as a naked and impolitic right, condemned by the enlightened conscience and judgment of modern times. Better opinion is that executed contracts such as the debt in this case, although existing prior to the war, are not annulled or extinguished, but the remedy is only suspended, which is a necessary conclusion, on account of the inability of an alien enemy to sue or to sustain, in the language of the civilians, a persona standi in judicio."
• The disability of an alien enemy to sue is considered in 31 Harv. L. Rev. 470 The effect of war upon contracts is considered in the printed hearings before the sub-committee of the Committee on Commerce of the Senate on H. R. 4960, 65th Congress, First Session, and in Senate Report No. 113, 65th Congress, First Session. Much of this material is reprinted in 2 Clark on Receivers, Sec.Sec. 1237 et seq.
10 In Halsey v. Lowenfeld,  2 K. B. 707, it was held by the Court of Appeal that where the lessee under a lease made before the outbreak of war becomes an alien enemy on the outbreak of war, his covenant in the lease to pay the rent is not thereby extinguished or suspended, and he may be sued for the rent that accrues due during the war. If such a lessee has assigned the lease taking a covenant of indemnity against liability for the rent, his remedies are suspended whilst he is an alien enemy, so that he cannot during the war enforce his right to indemnity. Lord Reading, C. J., said (p. 712):-"That commercial intercourse between inhabitants of this country with alien enemies, unless permitted by the Sovereign, is prohibited and illegal is beyond question. See The Hoop, 1 C. Rob. 196; Esposito v. Bowden, 7 E. & B. 763,779; Porter v. Freudenberg, , 1 K. B. 857, 867. And this prohibition at common law of intercourse between residents in this country and aliens is not confined to commercial or trad- An irrevocable power of attorney given by one not at the time an alien enemy is not invalidated when he becomes such, and an agreement entered into by an attorney which does not involve trading with the enemy is enforceable;11 but the result would be otherwise if exercise of the power necessarily involved commercial intercourse with the enemy.12