Whakakihia te rerenga e whai ake nei: I tohaina ki te 21st Infantry Regiment, i mahi a McAndrew i te hauauru o te United States, a i uru ki te Pakanga Kanikani Wairua ki te Sioux i te 1890<unk>1891. I whakatairangahia ia ki te rangatira tuatahi i te tau 1894, a ka tohaina ki te 3rd Infantry. I mahi a McAndrew i Cuba i te Pakanga Paniora-Amerika, a, i uru ki te
Ko te Pakanga o El Caney me te Siege o Santiago. I te tau 1899, i whakatairangahia a McAndrew ki te rangatira, a ka mahi ia i nga Philippines i te Pakanga Philippines-American. Mai i te 1905 ki te 1906, i mahi ia me te 3rd Infantry i Skagway, Alaska.