“If all the states of Europe were to concur in framing a general code of international law, which should be binding on them all, and form themselves into a confederacy to enforce it, this might be regarded as a positive law of nations for Europe. But nothing of this sort has ever been attempted. The nearest approach to such international legislation is the general regulations introduced into treaties by the great Powers of Europe, which are binding on the contracting parties, but not on the states that decline to accede to them. “To settle disputes between nations on the principles of justice, rather than leave them to the blind arbitrament of war, is the primary object of the European law of nations. When war has broken out, it regulates the rights and duties of belligerents, and the conduct of neutrals. “As the weak side of the law of nations is the want of a supreme executive power to enforce it, small states are exposed to great disadvantages in disputes with their more powerful neighbours. But the modern political system of Europe for the preservation of the balance of power forms a strong barrier against unjust aggression. When the power of one great state can be balanced, or kept in check, by that of another, the independence of smaller states is in some degree secured against both; for neither of the great Powers will allow its rival to add to its strength by the conquest of the smaller states.... “By the declaration of 16th April 1856, the Congress of Paris, held after the Crimean war, adopted four principles of international law. 1. Privateering is and remains abolished. 2. The neutral flag covers the enemy’s merchandise, with the exception of contraband of war. 3. Neutral merchandise, with the exception of contraband of war, is not liable to seizure under an enemy’s flag. 4. Blockades, in order to be binding, must be effective; that is to say, must be maintained by a force really sufficient to prevent approach to an enemy’s coast. This declaration was signed by the plenipotentiaries of the seven Powers who attended the Congress, and it was accepted by nearly all the states of the world. But the United States of America, Spain, and Mexico, refused their assent, because they objected to the abolition of privateering. So far as these Powers are concerned, therefore, privateering—that is, the employment of private cruisers commissioned by the state—still remains a perfectly legitimate mode of warfare. Britain and the other Powers who acceded to the declaration, are bound to discontinue the practice in hostilities with each other. But if we should have the misfortune to go to war with the United States, we should not be bound to abstain from privateering, unless the United States should enter into a similar and corresponding engagement with us....