The American K-9 corps , Lemish said , really began during World War II , when , among other tasks , thousands of dogs donated by civilians patrolled shorelines . Several thousand people will gather together at a War Dog Memorial in California . Of the more than 4,000 dogs who served in Vietnam , only about 200 came home . Dogs , many of them euthanized , help to rescue more than 500 casualties , historian says . In 1970 , the U.S. changed policy , setting up a military service dog adoption program .
Several thousand people will gather together at a War Dog Memorial in California . Of the more than 4,000 dogs who served in Vietnam , only about 200 came home . Dogs , many of them euthanized , help to rescue more than 500 casualties , historian says . In 1970 , the U.S. changed policy , setting up a military service dog adoption program .