Mezue ahịrịokwu na-esonụ: N'afọ 1911, mgbe ọ nọ na Fort Sam Houston, Texas, Hickam natara ọzụzụ ịnya ụgbọelu na mgbakwunye na ọrụ ndị a na-ekenye ya mgbe nile. N'ọnwa Jenụwarị afọ 1914, a kpọfere ya na ndị 8th Cavalry, mgbe ahụ na Philippines, bịarutere Camp Stotsenberg na Disemba afọ 1913. Mgbe otu afọ gachara, e buliri ya n'ọkwa lieutenant nke mbụ na 7th Cavalry, na Camp Stotsenberg, wee laghachi na 7th Cavalry na United States na Disemba 1915 na Douglas, Arizona. O jere ozi na Mexico dị ka akụkụ nke
Ọ hụrụ ọgụ na Machị 19, 1916 na Guerrero; Eprel 22, na Tomochic, Chihuahua, ebe e nyere ya Silver Star na ọgụ megide Villistas nke Candelario Cervantes duziri; na Piojo Canyon na June 20. Na Nọvemba 1916, Hickam hapụrụ 7th Cavalry ka ọ rụọ ọrụ dị ka Prọfesọ nke Sayensị Agha na Mahadum nke Maine wee nweta nkwalite ka ọ bụrụ onye isi nke ndị agha na-agba ịnyịnya, na Mee 1917, mgbe United States banyechara Agha Worldwa Mbụ. Ọ sonyeere 18th Cavalry na July, mana a gbanwere ngalaba a ka ọ bụrụ ogbunigwe.