Australian/American Signals cooperation was not only important in stopping the Japanese advance to Australian shores but marked the beginning of Australia embedding its forces with the United States rather than simply furnishing troops for the British. Whilst the British, in my opinion , had a long history of using Commonwealth troops to either protect their colonial interests or to take on deployments with high expected rates of attrition, when Australia faced the real possibility of invasion with the vast majority of its troops and equipment deployed overseas, it was the Americans, whose interests in the Pacific aligned with our own, that were on hand to push the Japanese back from our shores. The Battle of the Coral Sea saw the beginnings of the deployment of Australian sea power under direct American command, a joint approach that would continue to the present time – it was, however, Signals Intelligence that led the way to the embedding of US/Australian forces and played a major