You’re working under the assumption that the person in question would be looking at his fellow men to get aroused in the first place. Ok put yourself in the shoes of the said 'gay' person. Example: Been on an exercise, taking a shower, ready to eat some food. Do you really think that this person is going to ruin his chances of being in the army by doing something inappropriate?
So are u saying that no straight guy in the army would ever get aroused? Based upon your comments does that mean only gay people are likely to get aroused in the army? Incidents could happen for straight and gays but most people would give a little more thought to letting themselves get that way in the first place through fear of rejection, being embarrassed etc.
Being unfair is one thing, assuming someone will do something sexual to ruin their career is another. Ok another example; you’re a straight pool attendant watching the females in a pool as part of your job; are you going to get aroused and stand there in your shorts saluting as the girls walk past, erm no. Self control, respect for others always plays apart plus it might not even cross someone’s mind to get frisky. If you did something inappropriate you would be kicked out of your job, both genders would not like you and you would most likely end up in court and branded a pervert. If a person (gay or straight) did something inappropriate then the necessary action should be taken against them otherwise if nothing happened let them get on and do the job.
So the fact that someone who is gay cannot save lives. Ok the post relates to a general in charge of men, did he let men die under his control; in the field or elsewhere due to his sexual orientation? Did it affect his judgement as a soldier and ability to undertake his job? What happened before the gay issue was brought up; did gays in the past fight alongside straight people or is this totally new?
The difficulty you are having is that you assume everything would rotate around sex, reality check it doesn't. Once people believed in witches and persecuted them but after that myth was kicked into touch there's be no ritual burnings taking place on a frequent basis now has there?
I understand your point but I don't agree with what you are saying overall.