 He became a close friend of antisemitic propagandist James True and distributed "subversive" literature from George Deatherage’s Knights of the White Camellia and William Dudley Pelly's Silver Shirts.In 1939, he was ordered to attend the Army War College in Washington, D.C. and after graduating was named executive officer of the Division of Plans and Policies, USMC.On March 1941, del Valle became the commanding officer of the 11th Marine Regiment, (artillery).