Faatumu le fuaiupu lenei: Mai le 1942 i le 1946, i le taimi o le Taua Lona Lua a le Lalolagi, na avea ai McKeithen ma lutena muamua i le vaega o le 77th Infantry Division, United States Army i le Pacific Theater of Operations. Sa tau o ia i taua i Guam,
O le Fagaloa o Leyte, Ie Shima, ma Okinawa. Na ia mauaina ni pine se lua o le Bronze Star Medal ma le Distinguished Service Cross.