I te tau 1911, i a ia i Fort Sam Houston, Texas, i whakaakona a Hickam ki te rere hei taapiri ki ana mahi kua whakaritea. I te marama o Hanuere 1914, i whakawhitihia ia ki te 8th Cavalry, i reira i nga Philippines, ka tae ki Camp Stotsenberg i te marama o Tihema 1913. I te tau i muri mai ka whakatairangahia ia ki te whakakii i tetahi waahi tuatahi i te 7th Cavalry, i Camp Stotsenberg, ka hoki mai me te 7th Cavalry ki te United States i te Tihema 1915 ki Douglas, Arizona. I mahi ia i Mexico hei wāhanga o te Mexican Punitive Expedition
I kite ia i te mahi i te Poutu-te-rangi 19, 1916 i Guerrero; Paenga-whāwhā 22, i Tomochic, Chihuahua, i whakawhiwhia ai ia ki te Whetu Hiriwa i roto i te mahi ki a Villistas i arahina e Candelario Cervantes; me Piojo Canyon i te Pipiri 20. I te marama o Noema 1916, ka wehe atu a Hickam i te 7th Cavalry ki te mahi hei Ahorangi mo te Pūtaiao Hauora i te Whare Wananga o Maine ka whakawhiwhia ki te rangatira o te Cavalry, i te marama o Mei 1917, i muri i te urunga mai o te United States ki te Pakanga Tuatahi o te Ao. I uru atu ia ki te 18th Cavalry i te marama o Hurae, engari i whakahoutia tenei waahanga hei patu patu.