The normalizing of imperialistic murder abroad is not an anomaly; it is a core part of US identity. The US itself is a product of imperialistic murder, its crowning achievement even.
To this day US soldiers deployed abroad use the term “indian country” to designate occupied territory where they conduct counter-insurgency operations. That term dates back to counter-insurgency operations conducted by the very same institution against Native Americans until 100 years ago. What was once abroad is now domestic - such is the nature of empire.