Media blackout

Media blackout refers to the censorship of news related to a certain topic, particularly in mass media, for any reason. A media blackout may be voluntary, or may in some countries be enforced by the government or state. The latter case is controversial in peacetime, as some regard it as a human rights violation and repression of free speech. Press blackout is a similar phrase, but refers specifically to printed media.

Media blackouts are used, in particular, in times of declared war, to keep useful intelligence from the enemy. In some cases formal censorship is used, in others the news media are usually keen to support their country voluntarily as in the UK D- (later DA-)Notice system in the Second World War.

Some examples of media blackout would include the media bans of southern Japan during the droppings of the atomic bombs on Hiroshima and Nagasaki, and the lack of independent media correspondence from Iraq during the Persian Gulf War.

During World War II, the US Office of Censorship sent messages to newspapers and radio stations, which were acted on by recipients, asking them not to report any sightings or explosions of fire balloons, so the Japanese would have no information on the balloons' effectiveness when planning future actions. As a result, the Japanese learned the fate of only one of their bombs, which landed in Wyoming, but failed to explode. The Japanese stopped all launches after less than six months. The press blackout in the U.S. was lifted after the first deaths from fire balloons, to ensure that the public was warned, though public knowledge of the threat could have possibly prevented the deaths. News of the loss of over 4,000 lives when UK ship RMS Lancastria was sunk during the war was voluntarily suppressed to prevent it affecting civilian morale, but was published after it became known overseas.

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