He then saw service in California and Maryland, until, after the American entry into World War I, he was ordered to the Western Front with the 11th Infantry Division. However, the Armistice with Germany on November 11, 1918 was signed before the division saw any action. The division was ordered back to the United States and then deactivated at Camp Meade, Maryland. Hobbs was then assigned to the USMA, where he served as an assistant instructor of tactics until 1924.