Vengence film - early eighties
 

There was a film that I recall seeing back in the early eighties. The plot starts with two American soldiers in Vietnam working with an ARVN officer. They wind up betraying the ARVN officer over I can't remember what. They injure him but leave him alive. Years later, the ARVN officer comes to America with the intention of getting even. Might have been the late 70's. What was the title of that film?