Dogs for Defense was a World War II (1939-1945) military program that involved American citizens who were asked to donate their pets for the war effort. Initially various breeds of dogs were requested, but only if they were pure bred. They could be of either sex, but had to be between one and five years old and exhibit watchdog traits. They also had to pass a physical inspection. When donated, the dogs were trained and used to guard and patrol duties. When the war ended, the dogs were deprogrammed and returned.

Prior to World War II, the United States military did not have a formal K-9 corp (K-9 represented the word canine) and owned fewer than 100 dogs, mostly sled dogs in Alaska. Subsequent to the Japanese bombing of Pearl Harbor on December 7, 1941, the United States military began using dogs.

Historically, dogs have been used to fight in wars since Roman times, if not earlier. The first modern army to employ dogs trained as messengers, scouts and sentries was the German Army, in the later 19th century. They used dogs again in WWI, as did the British and French armies.

According to Fairfax Downey in his book ‘History of Dogs for Defense’, in 1946, the German Shepard was named by the War Department as the official U.S. Army dog.

Today, all branches of the United States Armed Forces employ military working dogs (MWD), They are used to detect improvised explosive devices (IEDs), narcotic detection plus as companions in the rehabilitation of wounded soldiers.

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