Soldiers of misfortune would more likely be my read ? I met a few old yanks in places like soi cowboy, pattaya and other parts of SEA in the 1990's who had never went back home after Vietnam, always wondered their stories.
My sis, bit of a traveller, married into a family, her sister in laws first husband was supposedly a German businessman, went missing on a business trip abroad, never seen again, I remember looking in his office and finding a pile of SOF mags and a bookcase full of Jane's weapons directories,.