Re. the 'life at stake' situation.
For a very long time, from the dawn of warfare I suppose, the infantry has been seen and treated as a killing machine. Go out there with a weapon, kill, come home. It has suited both the military and society to maintain this point of view. Yet we have seen, certainly from WW1 onwards, that close combat certainly does affect the human mind, whether females are there or not. I'd opine that although a male may admit to being more affected, likely to 'break', if a female colleague is threatened, the same psycological scars will be present should a male colleague be in a similar position. It might be easier for the individual to accept, justify even, but the symptoms of mental trauma will be there and will eventually surface. If you have been part of a close knit team of males, training, living, fighting together, with common beliefs and for a common goal, would you honestly say that just because your brother in arms were a male you would accept his torture and murder? So, no, ultimately I don't think it will make a long term difference.