I have to disagree with you here. I KNOW my free ranging cocks have chased off hawks and fox, at least long enough for the ladies to find cover and the guard animals to come take charge of the situation. I have heard of many others that have given their lives trying to protect their flock. The key is to get a breed that still has the proper protective instincts. Most hatchery stock has been bred only to maximize egg and/or meat production and therefore have lost many of their natural instincts. The same with show stock that has been bred to meet a narrowly defined visual standard (SOP). Many of the cocks from landrace breeds still have these natural instincts and can be a definite asset to a free ranging flock. It is also so much fun to watch them find food for their girls and call them over to eat it.A rooster really doesn't do that much good. Some will abandon ship at first sign of danger. A good roo is one that sounds the alarm so his hens can try and hide or run. Roos don't stand a chance standing up to most predators. They will killed and then are no help at all.

As to the original issue of hens feeling safe again, adding hiding places to their run or range will help. The closer they are to a place they can hide if need be, the safer they will feel. Wide open spaces are intimidating, especially after an attack.