Blockade is the patrolling of an enemy country’s coasts by warships and planes to keep the country from receiving goods it needs to wage war. Nations with adequate naval forces can use the blockade to keep their enemies from getting arms, munitions, and even food from neutral countries.
No nation has the right to declare a blockade unless it has the power to enforce it, according to international law. This rule was established by the Declaration of Paris at the close of the Crimean War in 1856. Other rules for blockade were set down in the Declaration of London in 1909. This stated that a country must declare a blockade formally and must notify neutral nations. The Declaration of London also provided that a blockade must not be extended beyond the coasts and ports belonging to or occupied by an enemy.
A different kind of blockade, used by both Britain and the United States in World War II, was the blacklist. This listed business firms and individuals in neutral countries who were trading with the enemy. The companies and individuals on the blacklist were not allowed to buy goods from the United States or Britain. Some authorities considered this a form of blockade because it kept Germany, Japan, and Italy from getting goods which could otherwise have been bought for them by neutrals.
Paper blockade
is a blockade which has been declared by a nation that does not have the power to enforce it. Napoleon declared such a blockade against Britain in 1806, and Britain declared one in return against France (see Continental System ). Both countries then seized neutral vessels for their own use. The German submarine blockade of the United Kingdom and Ireland in World War I was considered by other countries to be a paper blockade. A real blockade is established only when an area is guarded by a naval force so large that a merchant ship finds it almost impossible to “run the blockade” and bring a cargo into the affected area.
Pacific blockade
is a blockade established in peacetime. President John F. Kennedy ordered a pacific blockade of Cuba in 1962 to halt shipments of missiles to that country (see Cuban missile crisis ). A nation may also use a pacific blockade to force another nation to do what it wants. In this case, the blockade applies only to ships of the nation being blockaded. Many international law authorities believe such a blockade is not legal.
