Nah man Killmonger was a product of his environment and his situation. The day that T'Chaka murked N'Jobu was the day that his fate was sealed. They left him behind and from that point it was a wrap. They said son was a Naval Academy graduate at 19, MIT grad, Navy Seal and part of a Zghost unit.
None of those were to serve his country, they all served a purpose in meeting T'Chaka/T'Challa and washing them and taking the throne for himself. Anyone who says that those kills in the line of duty were justified is just as twisted as son himself. Once he joined that Ghost unit he was basically a mercenary with extremely lose ties to state, which I'm sure fit his personality and motive better than being serviceman. Homie definitely has zero regard for life, was talking about killing children, opressors or not that is not a hero or anti-hero in the least bit. he gave himself his damn name just cuz he liked racking up confirmed kills. he made a lot of valid points but his motives were ultimately that of a kid hurting for his pops.
I feel like the heart shaped herb scene was meant to convey that. dude was a tactician on the exterior but he never really got the chance to grow up and instead had to let all that hate and death basically raise him.