I'm struggling to find any moral justification for the US drone program after reading an article like this. I guess the argument is the trade-off between the li

I'm struggling to find any moral justification for the US drone program after reading an article like this. I guess the argument is the trade-off between the lives of the civilians killed and the operators who are impacted versus the damage done by the enemy combatants. But it seems impossible to measure those trade-offs accurately. Are there any philosophical/ethical frameworks that take this on?