Blockade

a stoppage of legal commercial intercourse with the ports of an enemy. In time of war it is considered legitimate to prevent the ships of neutral nations from visiting the coasts and entering the ports of an enemy. International law requires that due notice shall be given. This warning may be conveyed to neutral governments by a general diplomatic notification, or warning may be given to individual ships. It is a breach of international law for a shipowner to attempt to pass in or out after a blockade has been established. If caught by the patrolling ships of the blockading power, the ship may be confiscated. The cargo goes with the ship, unless the owner can prove that he is not the owner of the ship, and that he did not know that his cargo was running the blockade, or intend that it should do so.

In order that a blockade may be recognized by neutral nations, it must be made effective. If we were at war with Mexico and were to notify the nations that the coast of Mexico was in a state of blockade, and yet patrol the coast with an inadequate force, say a single warship, this condition of affairs would be held to be what is known as a paper blockade. If our single ship happened to capture a merchant vessel carrying the British flag, for instance, the government of Great Britain might very properly insist that the ship be restored to its owner, on the ground that the blockade had not been made effective. To make a blockade effective it is necessary to patrol the coast in question and guard the harbors with enough ships to make it dangerous to attempt to go in or out.

During our Civil War our government notified all foreign countries that the ports of the South were in a state of blockade. Warships were sent to patrol the harbors. For a time blockade running to bring out the cotton much needed by English mills was a hazardous but profitable occupation. The headquarters of the blockade runners were in the Bahama Islands. Business rose from a few thousands a year to $23,000,000 during this period. After the blockade became more effective, English ships were shut out entirely, and cotton was burned to prevent its falling into the hands of federal troops.

The most striking blockade of modern times was declared during the wars between France and England at the beginning of the last century. Napoleon gave Prussia Hanover as the price of closing Prussian ports against English ships. Prussia had a perfect right to do so. England, by way of retaliation against Prussia and France, declared the coast from the mouth of the Elbe River to Brest under blockade. As a matter of course it was impossible for England to maintain this blockade; but nevertheless British vessels were able to cause coastwise commerce infinite annoyance. It was dangerous to enter a port or leave a port through that entire stretch of coast. In 1806 Napoleon issued his famous Berlin decree declaring the entire British coast in a state of blockade. He forbade the ships of all nations to enter British waters. England returned with the no less noted "orders in council," extending the blockade already declared, forbidding the ships of any nation to enter or leave continental ports from Italy to Prussia. These blockades were of little value to either England or France. They caused great distress. The owners of ships carrying neutral flags were obliged to tie up lest some French or English men-of-war should confiscate them. Ships were afraid to sally out; trade languished; merchants were distressed; goods spoiled for want of transportation. These blockades came to an end, of course, even before the close of the Napoleonic wars. In 1856 the Congress of Paris undertook to prevent the occurrence of useless and harassing blockades. It was decided by this Congress that in the future due notice of a blockade must be given, and that to be valid the blockade must be rendered effective. The rules thus laid down are now recognized as international law.

See Alabama Claims