In 1968, he was appointed to be Principal Deputy Assistant Secretary of Defense for International Security Affairs and was a protege of Paul Nitze. Earle served as the Defense Advisor to the US Mission to NATO from 1969 to 1972.
In 1968, he became the Principal Deputy Assistant Secretary of Defense for International Security Affairs under Paul Nitze’s guidance and served as the Defense Advisor to the US Mission to NATO from 1969 to 1972.