The rights and duties incident to neutrality is a branch of international law that is of comparatively recent growth. Still the distinction between belligerent nations and neutral nations and between enemy goods and neutral goods has been recognized from quite early times. In the well-known collection of maritime law known as the Consolato del Mare, which made its appearance in the fourteenth century, the rule is laid down that enemy goods on neutral ships are liable to capture, but neutral goods on enemy ships must be restored to their owner. This rule evidently assumes also the existence at that time of the belligerent right to visit and search neutral vessels.

No exhaustive study has, as yet, been made of the Napoleonic era with a view of determining the exact legal status of the blockades established by the British orders in council and the French decrees. It is the purpose of this work to point out the more salient features embodied in the principles of blockade during this period as set forth and laid down by the statesmen of the United States, Great Britain and France, together with their relations to the principles of international law. With this end in view, the treaties, conventions and diplomatic intercourse between the United States and these two foreign countries have been carefully studied. The opinions of statesmen and official legal counsel, as well as the diplomatic correspondence and the decisions of the admiralty courts must be accepted as, in a large measure, establishing the international principles upon which the legality of the various acts may be determined. Court decisions during this period, however, are too much influenced by expediency, made necessary by the demands of the times, to be unconditionally accepted as the last word on the legality of the points in question; but they will nevertheless be freely used.

The members of the Central American Peace Conference, held at Washington in 1907, primarily intent upon devising all possible ways and means of maintaining permanent peace in the Isthmus, sought to introduce into the treaties which resulted from the Conference not only those means and recourses which experience had shown would preserve good understanding and harmony among the five states, but, more particularly, they endeavored to find new methods which would strengthen the desideratum of the Conference by eliminating the causes of civil or interstate wars which might in the future occur in the Central American countries.

Naturally, the arsenal to which the Conference had to turn for the new arms to combat the causes of and prevent all war and revolution, could be none other than historical experience and the principles of international law.

The extent to which belligerents may interfere with the commerce of neutrals, on sea or land, has been in all wars a question of warm and continued dispute. A powerful belligerent is apt to proceed lawlessly, and a powerful neutral is apt to claim more rights than the authorities concede. It could-not be expected that the present state of war, involving every first class Power in the world, except the United States, and many of the lesser states as well, would be free from such complications, and this expectation has certainly been realized.

It would be improvident to undertake the discussion of so broad a topic as the whole of this controversy. This writer has several times, before considerable assemblies and in various publications, ventured to express his opinion on one limited portion of this dispute, namely, as to the right of neutrals to export munitions of war to belligerents and the extent to which the other belligerents are entitled to complain of or interrupt such trade.