BLOCKADE. To blockade a port is to close the port to the entrance and exit of all traffic by sea. The right to es tablish a blockade exists only in time of war and may be exercised only by a BELLIGERENT (q. v.) and only against the ports of the opposing belligerent. Its purpose is to cut off the communications of the blockaded enemy and to prevent him from receiving supplies or re-en forcements and from engaging in com mercial or military exchanges of any kind. The restrictions of a blockade weigh heavily not only upon the blockaded belligerent, but upon the neutrals desir ing to trade with him. In the interest of such neutrals, the limitations and restrictions provided by international law are many and are strictly enforced by the "prie courts" which determine the validity of captures of neutral ships in time of war. A blockade, to be legal, must be announced with such publicity as shall insure its reaching all interested neutrals, and must be maintained by such forces and in such manner as shall make it effective. An "effective" block ade has been defined as one which re sults in serious danger of the capture or destruction of any vessel attempting to violate it. The mere fact that a ves sel succeeds in passing the line of block ading ships does not prove that the blockade is not effective. But if en trance or exit can be made with some thing approaching impunity, the block ade is not legal and no penalty will lie against a ship charged with violating it.
Violation of blockade is not a crime, even in the eyes of the belligerent blockader; nor are the persons found on board a ship which is captured while attempting to "run" the blockade sub ject to treatment as prisoners of war. The ship and cargo are, however, sub ject to confiscation. To this rule there are modifications. A neutral ship which is actually in a port when the notifica tion of blockade is received is allowed a reasonable time to withdraw, without penalty. Similarly, a ship which has sailed for a certain port which is not blockaded at the time of the sailing but which is placed under blockade before the ship in question reaches it, is not subject to penalty for attempting to en ter the port in good faith and while still in ignorance of the blockade. Such a ship is not permitted to enter, but is told of conditions and directed to with draw. If she again attempts to enter, she is a lawful prize if captured. Simi larly, if it can be proved that the ship after sailing has received news of the blockade, as may well happen in these days of radio communications, she is a lawful prize if captured while attempt ing to enter. Still further, a ship which sails for a port known to be blockaded is a lawful prize if captured at sea while thousands of miles distant from the port. The intent to violate the blockade is in fact to violate it. Conversely, a vessel which has successfully passed the block ade outward bound is a lawful prize if captured before reaching her port of actual, not alleged, destination. The taint of violated blockade adheres to the cargo even though it has been trans ferred to another vessel, if the transfer has been made with a view to evading the penalty. During the American Civil War, it was a common practice for Brit ish ships with cargo destined for block aded Confederate ports to clear for Nassau or Bermuda, British ports near the Confederate coasts, and from there to begin what they proposed to regard as a new voyage to the nearest Confed crate port. Thus during the long run
across the Atlantic, they counted them selves safe from capture because bound for a British port and in danger only during the short run from Nassau, for example, to the coast of Georgia or Florida. Similarly, small fast vessels loaded with Confederate cotton would slip out of port, often in a fog, and if they succeeded in eluding the blockading forces would make a dash for Nassau and there trans-ship their cargo to other vessels which then sailed for England, claiming immunity from capture as British ships bound from one British port to another. To meet this subter fuge, the United States courts an nounced the doctrine of "continuous voy age," in which it was held that a cargo bound to or from a blockaded port did not lose the taint of violating the block ade either by breaking its voyage at an intermediate port or by transfer to an other vessel. This doctrine was ulti mately accepted by the British authori ties as sound and is now a recognized principle of international law.
The pressure of a blockade, if con ditions are such that it can be made complete, is often more compelling than the more directly exerted pressure of a military force. The blockade of the Confederacy during the Civil War prac tically sealed every port from Wilming ton, N. C., to the mouth of the Rio Grande; and the South, thus thrown back upon its own very limited agricul tural, industrial, and financial resources, was reduced to submission, not alone, as is generally supposed, by the victories of the Northern armies, but to almost a greater degree by the pressure of the naval blockade. It was the blockade of Germany by the Allied navies, not the successes of the Allied armies, that gave the Allies the victory in the World War. In each case, four years was required to bring about the exhaustion of the blockaded country, but in each case the end was inevitable from the beginning. And it is by the threat of blockade, dis guised under the term "economic pres sure," that it is proposed, in the latest plan for world peace, to compel govern ments to submit their grievances to ar bitration.
During the recent World War, the laws of blockade like those of "visit and search," "contraband of war," and many others of the laws of warfare on the sea as previously established in inter national law, were modified arbitrarily to suit the convenience of the parties to the war, under the plea that changed conditions made it impracticable to ad here to the old laws. It is true that many new conditions arose which had never been foreseen and that some devi ation from the letter of the law became, if not altogether justifiable, at least ex pedient and inevitable. It is to be hoped that a new Hague Conference may be assembled in the not distant future and new rules drawn up, if such are found desirable, covering many questions growing out of the war, and among them the question of blockade.