False flag

The contemporary term false flag describes covert operations that are designed to deceive in such a way that activities appear as though they are being carried out by entities, groups, or nations other than those who actually planned and executed them.

Historically, the term "false flag" has its origins in naval warfare where the use of a flag other than the belligerent's true battle flag before (but not while) engaging the enemy has long been accepted as a permissible ruse de guerre; by contrast, flying a false flag while engaging the enemy constitutes perfidy.

Operations carried out during peace-time by civilian organizations, as well as covert government agencies, can (by extension) also be called false flag operations if they seek to hide the real organization behind an operation.

In land warfare such operations are generally deemed acceptable in certain circumstances, such as to deceive enemies providing that the deception is not perfidious and all such deceptions are discarded before opening fire upon the enemy. Similarly in naval warfare such a deception is considered permissible provided the false flag is lowered and the true flag raised before engaging in battle:auxiliary cruisers operated in such a fashion in both World Wars, as did Q-ships, while merchant vessels were encouraged to use false flags for protection.

Such masquerades promoted confusion not just of the enemy but of historical accounts: in 1914 the Battle of Trindade was fought between the British auxiliary cruiser RMS Carmania and the German auxiliary cruiser SMS Cap Trafalgar which had been altered to look like Carmania. (Contrary to some possibly mendacious accounts, the RMS Carmania had not been altered to resemble the Cap Trafalgar.)

Another notable example was the World War II German commerce raider Kormoran which surprised and sank the Australian light cruiser HMAS Sydney in 1941 while disguised as a Dutch merchant ship, causing the greatest recorded loss of life on an Australian warship. While Kormoran was fatally damaged in the engagement and its crew captured the outcome represented a considerable psychological victory for the Germans.

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