This is an interview with embedded independent journalist Michael Yon who reported on one of his wounded tent mates who died after having to wait for an army medivac helicopter that was nearby but could not come to his rescue. According to Yon, the nearby helicopter could have flown and arrived quickly if did not have to wait for an armed escort to arrive before taking off. The Army medivac rescue helicopters aren't equipped with defensive .50 machine guns because they have red crosses on their sides, and the Geneva Convention prohibits anything with a red cross from being armed.
Since we know that the Taliban does not respect red crosses, and probably uses them as cross hairs when firing rocket propelled grenades at the medivac helicopters, you would think that someone with command level decision-making authority would figure out that it would make sense to take the red crosses off the medivac choppers and equip them with defensive guns so that they can get to the wounded soldiers faster and save more lives. No such luck.