Every country treats their citizens differently than non-citizens, and every country believes surveilling and killing non-citizen combatants in an armed conflic

Every country treats their citizens differently than non-citizens, and every country believes surveilling and killing non-citizen combatants in an armed conflict is perfectly acceptable -- and that's what the government of the United States believes it's doing. You may disagree with the government of the United States' definition of combatant or armed conflict, but once you grant them that belief, they're not acting differently than any other nation.